Architecture explorer / Microsoft Foundry

Three ways to build.
Eight patterns to build and operate voice.

Choose how much conversation logic and lifecycle you want to manage.

Voice Live is the runtime in all three paths. The difference is where your agent lives.

Start with a pattern. Then watch the enterprise request flow.

01 / You own the orchestration

Voice Live API

Real-time speech with an application-controlled session and optional custom agent.

Voice Live APIAudio + conversation model
Your application / agentOptional agent, hosted by you

Use when: custom orchestration and session control matter most.

Explore custom orchestration →
02 / Add voice to what exists

Voice Live +
Foundry text agent

Preserve the text agent's tools and knowledge; add a managed speech layer.

Voice LiveSpeech recognition + synthesis
Foundry Agent ServiceExisting text agent + tools

Use when: an existing Foundry agent already solves the business problem.

Explore the integration →
03 / Managed voice lifecycle

Foundry voice agents Preview

A voice-native agent definition, with Voice Live inside the managed experience.

Foundry voice agentOne versioned agent definition
SpeechVoice Live
ModelRealtime or text
ToolsKnowledge / APIs
ObserveTraces / evals

Use when: you want managed voice configuration, versions, and channels.

Explore a native voice agent →
Preview: validate before production8 interactive reference architecturesReviewed October 16, 2026Compare the supported paths
Native voice agents / Preview

Speech-first.
Agent capabilities.
One managed lifecycle.

What the new agent experience adds beyond a manually assembled voice session.

Four capabilities to discuss before choosing an architecture. Quickstart [2]

Speech-first by design

Create for conversation

  • Select Voice interaction mode at creation.
  • Configure turn detection, interruptions, audio, and voice.
  • Add supported locale, custom voice, or avatar options.
ListenTake turnsSpeak
Model and pipeline choice

Your reasoning, your speech

  • Supported native speech-to-speech models.
  • Text models with speech recognition and synthesis.
  • Compatible self-deployed models and MAI speech options.
See the pipeline map →
Familiar development surfaces

Portal, SDK, and CLI

  • Browser playground for voice testing.
  • Supported Python, JavaScript, and .NET SDK paths.
  • Azure Developer CLI configuration and lifecycle workflows.
Configuration surfaces [4]
Build / Release / Operate

Agent lifecycle, not just audio

  • Knowledge, tools, and immutable agent versions.
  • Voice-pipeline traces, monitoring, and evaluation.
  • Supported browser sharing and phone channels.
Channel-specific limits [7]   Voice tracing [9]

Important: voice-agent preview is not a production SLA. Audio/transcript capture is opt-in, not automatic. Teams Phone connectivity is not the same as publishing a Teams app.

Explore / Animate / Inspect

Enterprise architecture studio

Select a pattern, play the request, or click a component to inspect its implementation.

Design simulation, not a live deployment
A language-aware implementation

Different languages. The same business contract.

Localize listening and speaking. Keep business identifiers, validation, and authorization stable.

1 / RecognizeEnglish / en-US
2 / ExecuteCanonical order ID + caller authorization
3 / RespondLocalized English voice

Authored language examples, not live translation or audio. Model, recognizer, voice, code-switching, and region compatibility must be tested separately. Language support

Animate the multilingual architecture
Order support / illustrative
CallerWhere is my order 1042?
get_order_status({ "orderId": "1042" }) // Authenticated identity is supplied by the server.
AgentOrder 1042 is in transit. Expected delivery is Friday.

Language selection never changes who may access the order. Use an explicit language confirmation or fallback when detection is uncertain.

One Voice Live runtime / several configurations

Where does audio become text?

Three audio-processing paths, plus a bring-your-own-deployment option. The model and speech configuration change; the business tools can remain the same.

1 / Native speech-to-speech

Direct audio reasoning and audio response. Evaluate naturalness and tool reliability.

Audio in
Realtime S2S modelSupported native audio model
Audio out

2 / Semi-cascaded

Native audio understanding, with a separately selected compatible Azure output voice.

Audio in
Realtime modelText for synthesis
Azure TTSCompatible output voice
Audio out

3 / Cascaded

Separate recognition, text reasoning, and synthesis. Useful for existing text-agent workflows.

Audio in
STTAzure / supported MAI
Text modelReasoning + tools
TTS
Audio out

4 / Bring your own model

A deployment choice, not a fourth audio transformation. Use a compatible native or cascaded path.

Voice LiveSpeech runtime stays
Your supported deploymentModel / capacity / allowed customization
Same toolsAuthorized business APIs

No universal latency or accuracy ranking is implied. Compare the same language, noise, tools, prompt, and concurrency. BYOM support is model/provider/API specific, not catalog-wide. Configuration [4]   Models [5]   Speech combinations [6]

Quick model guide: conversation, recognition, and synthesis
Native audio

Realtime conversation

gpt-realtime familygpt-realtime-mini family

Evaluate natural dialogue, tool correctness, interruption handling, and cost.

Model / region listing
Cascaded pipeline

Text reasoning

Supported GPT text modelsCompatible BYOM deployments

STT → text model → TTS. Useful for existing agents and specialist reasoning.

Managed versus self-deployed
Speech input

Recognition

azure-speechMAI Transcribe variants

Test vocabulary, accents, locale detection, noise, and streaming availability.

Compatibility guidance
Speech output

Synthesis

Azure neural / HD voicesMAI-Voice-2.1-Flash

Flash targets interactive speech. Verify voice, locale, consent, and latency.

MAI voice documentation

Enterprise-ready design is not the same as production-approved preview. Native voice agents and some speech models remain preview: no preview SLA, and not recommended for production workloads. These diagrams are reference patterns, not tenant-validated deployments. Private networking and data locality must be checked for the exact combination.

Web channel / who owns each signal?

The agent trace is not the whole web experience.

Yes: users talking through a web app still produce native Foundry voice-session traces when the project's Application Insights connection is configured. No: that connection alone does not instrument the browser, your backend, or your business APIs. Voice observability [9] / Trace setup [23]

BROWSER / YOUR CUSTOM APP

Did the user hear the reply?

Instrument microphone permission, connection startup/close, playback start, interruption handling, and client errors explicitly. Page views and HTTP dependencies do not measure live audio or WebSocket messages automatically.

App-defined events, not built-in Foundry metrics. Follow consent requirements and avoid raw audio, transcripts, tokens, and user identifiers in browser telemetry.

BACKEND + TOOLS / YOUR CODE

Did the business task succeed?

Instrument your session relay, authorized APIs, retrieval, and downstream dependencies with supported Azure Monitor/OpenTelemetry tooling. Record duration, failure category, agent version, and an opaque correlation key.

Tool-call telemetry in Foundry does not replace tracing inside the API. A successful model response is not proof that a database or CRM commit succeeded.

Browser experience events + Backend / API spans + Foundry voice-session trace → Application Insights + operational dashboards

Animate the web-app monitoring architecture →

Foundry preview web app

Use Channels > Preview web app when the endpoint supports it. Grant intended organizational users access, connect the project's Application Insights, then generate a fresh conversation and verify a voice trace.

You do not own that managed frontend's source or assume it exposes an SDK injection point. Test microphone/playback separately. If you need custom browser events and application dashboards, build and instrument your own client.

Supported sharing and access [7]

Your own web app

Instrument the browser and backend separately. For HTTP paths you control, configure supported W3C trace-context propagation and allowed CORS origins. Never forward credentials or correlation headers indiscriminately.

Keep a server-side mapping from an opaque application conversation ID to the voice session ID returned by the supported API/SDK and any trace ID you can obtain. Media/WebSocket paths do not guarantee automatic parent-child correlation; use a verified mapping or trace links instead of claiming one continuous trace.

Browser instrumentation [24] / Application tracing [25]

Privacy: operational traces, content capture, and recordings are three separate decisions

Operational telemetry

Collect durations, error categories, usage, and identifiers necessary for support. Configure telemetry sampling/retention and least-privilege access; ingestion and logs can incur costs.

Sensitive trace content

Transcripts, prompts, tool data, and audio references are not captured by default. Enable content capture only with an approved privacy policy. Application Insights holds telemetry/audio references, not the audio recording itself.

Conversation persistence

store:true persists transcripts, events, and raw audio together in voice-agent-owned storage. store:false does not disable operational tracing or browser logging. Review recording and trace-content settings independently.

Trace readers need Log Analytics Reader and, for protected tables, Privileged Monitoring Data Reader at the applicable scope. Ingestion identity, trace viewing, evaluation, and annotations are separate permissions. Never log bearer tokens, cookies, API keys, or sensitive business payloads. Access and recording boundaries [9] / Sensitive content controls [26]

Web-channel troubleshooting runbook and release checks
SymptomInspect firstThen verify
No voice traceProject Application Insights connection, recent traffic, ingestion delay, writer permissionsCorrect project/version, time range, reader RBAC, sampling and protected-table access
Agent trace is fast, user hears a delayBrowser playback start, buffering, device permission and network timingCompare client measurements with the precise service metric definition; browser speaker latency is not service TTFA
Slow turn or repeated answersVAD boundary, model, retrieval and tool waterfallTimeouts, retries, oversized context, throttling, and failed action recovery
Trace exists, no transcript/audio playbackContent-capture settings, available references, recording policy and playback accessDo not enable recording as a blanket fix; approve access and retention first
Browser/API spans are separateHTTP trace context on owned endpoints and opaque conversation-to-session mappingDo not assume WebSocket/media propagation; verify correlation with a known test call

Release test: a non-builder user completes a web conversation, interrupts it, denies microphone permission, encounters a failed tool, reconnects, and ends the session. Verify the corresponding client events, server traces, authorized API result, and retention behavior. Define latency/error/task-success alert thresholds from a measured baseline. Metric start/end points differ: the overall latency chart measures from end of VAD; do not label every TTFA signal as the same measurement. Metric definitions [9]

Architecture review: all eight patterns were checked against the linked Microsoft documentation on October 16, 2026. Boxes are logical responsibilities, not proof of separate deployed resources or network isolation. Browser diagrams show an example customer-owned relay; the managed preview web app's internals are not asserted. Speech stages are conditional on the model path, and caller identity must be bound to tool authorization explicitly. These are reviewed reference designs, not tenant-tested deployments.

Foundry voice-agent economics / preview

What does a Foundry voice agent cost to run?

Start with the native kind: voice agent, not a standalone Voice Live invoice. Model hosting determines the billing boundary; specialists, tools, channels, and retention complete the budget. There is no universal all-in per-minute price. Foundry voice-agent pricing [21]

Native voice agent: model + speech + Specialists + business tools + Phone channel, if used + App, monitoring + retention

Managed model: one voice component

model_type: managed bills model usage through the voice agent. Budget the configured model/speech path; do not add a second standalone LLM bill for the same usage.

Self-deployed: separate model spend

model_type: self_deployed bills inference to your compatible Foundry deployment. Speech/agent features remain additional. Existing PTUs are capacity to allocate, not free inference.

Agent architecture changes the total

Specialist delegation adds model/tool work; hosted specialists can add compute. Phone channels, avatars, retrieval, and opt-in recording have their own costs. Subagents [13] / Channels [8]

Foundry voice-agent budget planner

Illustrative budget, not a tariff. Voice-component amounts and service allowances below are editable assumptions, not published native-agent prices. Only the selected public text-model rates are sourced retail rates. Replace assumptions with your pilot's measured consumption and applicable quote. No inputs are saved or sent.

Changing the architecture loads illustrative delegation and phone assumptions. Explore this architecture
Self-deployed describes the model, not self-hosting the voice agent.
Used for phone cost and minute reporting, not voice token estimation.
Assumed primary model + speech; include all primary model turns. Not an Azure unit rate.
Assumption; includes failed/retried conversations in spend.

Voice/speech amounts are per conversation, not per-minute tariffs. If duration or turn count changes, re-estimate those amounts and the text-token totals.

Edit specialist, tool, phone, and operational assumptions
Assumed model/tool/compute subtotal, excluding work counted elsewhere.
API, MCP, or transaction costs; not primary LLM turns already counted.
Use your ACS or Twilio route quote, not both by default. Add number/licence fees to monthly spend.
Assumed allowance, not a Foundry platform fee. Include networking and evaluation budgets as needed.
$0 assumes store:false. With store:true, budget transcript, events, and raw audio together; trace capture is separate.
Enter the incremental quoted media cost if used.
Real model-rate examples: why the Foundry model choice matters
Self-deployed text-model inference only, not a complete voice-agent price. Global, uncached, non-batch token meters in the East US 2 USD retail listing, checked October 16, 2026. Example workload: 6,000 input + 1,000 output tokens across all primary turns per conversation. Source [22]
Model meter exampleInput / 1M tokensOutput / 1M tokensModel only / 1,000 conversations
GPT-4.1 nano$0.10$0.40$1.00
GPT-4.1 mini$0.40$1.60$4.00
GPT-4.1$2.00$8.00$20.00

The planner applies these rates only to its self-deployed token-billed text-model path. Confirm exact version, compatibility, capacity, deployment SKU, and regional/data-processing requirements. Cached, batch, fine-tuned, realtime/audio, and provisioned meters differ. More capable models may improve task completion; compare cost per successful task, not token price alone.

Foundry-specific cost controls and how to reconcile the pilot

Reduce repeated model work

Cap max_output_tokens; keep instructions and tool schemas short. Prefer static_interim_response where suitable: an llm_interim_response adds a model call on each trigger.

Design the agent to finish

Use end_conversation when the task is complete. Route only the calls needing a specialist; bound retries and tool loops. Long sessions and repeated context increase usage.

Measure native-agent costs

Inspect turn/session microsoft.foundry.voice.estimated_cost.* attributes: managed and self-deployed components, plus separate session avatar estimates. These are analysis estimates, not invoice records.

If conversations are stored, read the completed conversation's usage. Keep store:false unless retention is required; recording and trace-content capture need separate privacy decisions. Reconcile pilot estimates and all connected resources with Microsoft Cost Management. No zero platform fee or free preview is assumed here. Pricing and controls [21] / Tracing [9]

Secondary reference: direct Voice Live calculator and published meters

Use this comparison when choosing the direct API architecture. It is intentionally separate from the native Foundry voice-agent budget above; its meter bundles are not automatically native-agent tariffs.

Voice Live planning calculator

Example direct Voice Live meter bundles, East US 2, USD public retail snapshot checked October 16, 2026. Not a native Foundry voice-agent quote. Values stay in this page only.

Planning volume, not concurrent sessions
Shares must total at most 100; remainder is silence
Assumption; include prompt, tools, and repeated context
Add quoted tools, phone, or BYOM inference costs here
Illustrative $100 allowance, not a published platform fee

Approximation: 10 input audio tokens/second and 20 output tokens/second for the example OpenAI-family paths. Speaking time is a planning proxy; streamed silence, interruptions, replays, and actual metering can differ. Verify usage, billing meters, and caching with a pilot. [5]

Published meter examples, architecture cost differences, and how to validate the budget
Public retail API snapshot: East US 2, USD, Consumption, October 16, 2026. API prices returned per 1K tokens; values below are converted to per 1M. Selected base meters only, not every model/voice SKU. Source [20]
Meter familyNative audio in / outStandard speech in / outBase text in / out
Voice Live Pro$32 / $64 per M tokens$17 / $31 per M tokens$4 / $16 per M tokens
Voice Live Standard$11 / $22 per M tokens$15 / $26 per M tokens$0.66 / $2.64 per M tokens
Voice Live Lite$4 / $12 per M tokens*$15 / $25 per M tokens$0.11 / $0.44 per M tokens
Voice Live BYO standard speechNot covered by this row$12.50 / $23 per M tokensOwn model deployment is additional

*Meter availability is not model-capability proof: for example, the documented Phi path uses Azure speech output. Additional model-specific meters exist, including a Pro "LLM Text Output 2" meter at $24/M; use the meter mapping for the selected model rather than applying the base rate universally. Custom speech/voice, cached usage, avatars, and negotiated prices are not in this table.

Native voice agent

Budget the chosen managed or self-deployed model/speech path, tools, and channels. Confirm native-agent billing separately; this direct Voice Live calculator is not a universal native-agent invoice.

Voice Live + text agent

Account for Voice Live and the existing text-agent model deployment plus tools. Confirm actual meter boundaries so a bundled or separate model charge is not counted twice.

Specialists / custom hosting

Delegation adds model/tool calls; hosted code can add compute. Session length, verbose replies, retrieval context, concurrency, and retry storms can all change the total.

  1. Record exact architecture, model/deployment version, region, speech voice, channel, and expected concurrency.
  2. Get the applicable pricing/offer and model-to-meter mapping; public retail is not a contractual customer quote.
  3. Run a measured pilot. Use actual token, speech, tool, telephony, storage, and hosting consumption.
  4. Report cost per successfully completed task, not only per minute. Set a spend ceiling and review failed/retried sessions.

Azure Speech pricing   Microsoft Foundry pricing   Architecture billing comparison [3]

Research library: detailed comparisons, preview limitations, release guidance, and sources
01 / The executive explanation

Not a replacement for Voice Live. A managed agent experience on top of it.

Voice Live is the real-time voice runtime and API. Microsoft Foundry Agent Service adds an agent lifecycle: instructions, tools, knowledge, versions, monitoring, and governance. A native Foundry voice agent brings these together in a voice-specific definition. [1] [3]

A useful customer explanation: Voice Live gives the conversation a real-time voice. Foundry gives that experience a managed agent identity and lifecycle. The preview reduces orchestration work; it does not remove the need for application security, authorized tools, a usable client, or release testing.

Preview is a release decision, not a footnote. The voice-agent documentation identifies preview functionality as having no preview SLA and not recommended for production workloads. Validate feature access, region, channel, network configuration, and model support in the customer's actual project before committing to a design. Do not apply the availability status of the overall Foundry platform to every voice feature. [2] [4]

02 / Choose the integration pattern

Keep the working demo. Compare before you migrate.

There are three relevant patterns, not a binary choice between Voice Live and Foundry. The table distinguishes direct Voice Live from Voice Live connected to a text agent. [3]

Architecture comparison. Actual model, network, and channel compatibility still needs validation.
DecisionDirect Voice Live sessionVoice Live + Foundry text agentNative Foundry voice agent
Conversation engineSupported realtime or text model, configured through the session.Text model deployed for the connected Foundry agent; voice wraps that text experience.Supported speech-to-speech or text model, configured as a voice-agent version.
Configuration ownershipYour application owns session setup, instructions, and tool execution.Text instructions/tools in Foundry; voice/session settings are a separate integration surface.Model, greeting, voice, turn detection, and tools are managed together.
Enterprise toolsImplement and authorize application-side integrations.Reuse existing text-agent business logic, tools, and knowledge.Configure voice tools/knowledge, or delegate to a supported specialist subagent.
TelephonyBuild the provider/media integration or use a suitable accelerator.The application manages the telephony integration.Built-in provider connections and number bindings for Teams Phone extensibility and Twilio.
DiagnosticsInstrument the client and integration.Text-agent tracing does not include the full voice pipeline.Voice-pipeline spans, time-to-first-audio metrics, and optional conversation review.
Good fitCustom real-time UX and fine session-level control.Preserve a successful text-agent integration with minimal disruption.Evaluate managed voice orchestration, integrated operations, and voice channels in a controlled preview pilot.

What migration actually means

Create a new voice agent alongside the current agent. A text agent's interaction mode cannot simply be flipped to voice. Reapply effective settings, including client overrides, tool connections, and permission boundaries; then compare both experiences on the same tests.

Do not confuse this with classic-agent migration. Moving from the classic Agent Service to the new Agent Service is a separate lifecycle task. [3]

Reuse does not always mean a rewrite

A native voice agent can consult an existing prompt or hosted agent as a specialist. A hosted conversation engine is another option when custom code must own every turn, but it needs the required streaming bridge protocol, not just an ordinary text endpoint.

Constraint: voice subagents must be in the same project; they are not supported in VNet-isolated projects. [3] [13]

03 / What the experience can do

Listen naturally. Act deliberately. Make the result visible.

A useful voice agent is more than speech recognition plus a spoken answer. The conversational controls and business workflow must work together. These capabilities are configurable, not guarantees that every combination behaves identically.

Conversation

Turn-taking and interruptions

Silence-based or supported semantic turn detection determines when the user has finished. Tune pauses and interruption behavior for open-ended answers, accents, and noise. Barge-in also requires the client to stop or truncate buffered playback correctly. [4] [6]

Audio quality

Noise and echo handling

Noise reduction and echo cancellation help prevent background sound or the agent's own audio from becoming a new user turn. Test a headset, laptop speaker, and target phone path; a quiet playground test is not enough. [5] [6]

Experience

Greeting and latency masking

Use a fixed or model-generated opening. Interim responses can cover a slow tool call, so silence does not sound like a dropped session. A filler response does not reduce the actual tool's latency. [4]

Business actions

Functions, MCP, and toolboxes

Client-side functions require implementation in your app. MCP and versioned toolboxes support service-side execution; knowledge and tools such as Azure AI Search or OpenAPI can be attached through a toolbox. Validate supported authentication for each connection. [4]

Grounding

Answers based on approved content

Connect relevant knowledge instead of relying only on model memory. Retrieval must respect the user's authorization. Saying a document title aloud is not a substitute for showing provenance and validating source access in the application.

Agent knowledge integration [3]

Presentation

Transcript, voice, and avatar

Choose supported voices and locales; add an avatar for compatible browser experiences if it has business value. A phone call is audio-only. Transcripts, visible status, and a text fallback should be designed into the target client. [2] [7]

Business behavior is still designed. Recognizing already-covered topics, asking only missing questions, producing a valid schema, and requiring confirmation are not automatic product promises. Implement instructions, explicit state, tool contracts, server-side validation, and scenario tests. Cross-session memory and session recovery also need an explicit design.

04 / Model selection without the confusion

Separate the brain, the ears, and the voice.

A realtime model, a transcription model, and a synthesis voice are different choices. A speech model does not automatically provide business reasoning. A model's presence in the Foundry catalog does not automatically make it available in every voice project.

Conversation and reasoning models

Representative choices from current Microsoft documentation, not an exhaustive catalog. Tiers below refer to the direct Voice Live managed-model listing, not a universal Foundry voice-agent price or compatibility guarantee. Verify the selected native agent's model picker and supported deployment path. [5]

Use a full-quality candidate and a lower-cost candidate on the same workload before choosing.
Family / examplesRole and pipelineWhen to evaluateImportant qualification
gpt-realtime-2.1
gpt-realtime-1.5
gpt-realtime
Native realtime conversation; listed in Voice Live Pro.Open-ended, natural dialogue and tool-driven conversations.Global, data-zone, and regional variants exist for selected models. Their inference scope and region availability differ.
gpt-realtime-2.1-mini
gpt-realtime-mini
Smaller realtime family; listed in Voice Live Standard.A cost-conscious comparison for high-volume or narrower conversations.Measure quality and end-to-end latency. A smaller model is not automatically faster for every tool-heavy workflow.
phi4-mm-realtime PreviewMultimodal audio input with Azure speech output; listed in Voice Live Lite.Evaluate a lightweight alternative for constrained tasks.Do not assume capability parity with GPT realtime models or universal native voice-agent support.
azure-realtimeListed in Voice Live Pro with dedicated azure-realtime-native voices.Another documented realtime option when available to the resource.Dedicated voice compatibility matters; do not apply another realtime model's voice configuration unchanged.
gpt-4.1, gpt-4o
mini / nano variants where listed
Text reasoning with speech recognition and synthesis. Full models: Pro; listed mini variants: Standard; gpt-4.1-nano: Lite.Reuse a text-agent workflow; establish a familiar baseline for extraction and tools.Speech accuracy, text-model latency, tool time, and synthesis all contribute to responsiveness.
GPT-5 family
gpt-5, gpt-5.1, gpt-5.2, gpt-5.4
Cascaded pipeline; these examples are listed in Voice Live Pro. gpt-5-mini: Standard; gpt-5-nano: Lite.Complex instructions, multi-step business logic, and extraction scenarios needing stronger reasoning.Reasoning latency can hurt turn-taking. Keep spoken answers brief; delegate deep work only when needed.
gpt-5.6-terra
gpt-5.6-luna
Newer text-model entries in the current Voice Live list: Pro and Standard, respectively.Include only if the actual resource exposes them and an A/B test justifies the change.Current catalog examples, not claims about what was shown in the supplied video.
Compatible self-deployed models
Azure OpenAI, supported Claude / Fireworks / managed-compute models
Foundry voice agents can use supported customer model deployments. The service still hosts the voice orchestration.Reuse supported quota/PTUs, access more model choice, or use supported customization.Compatibility is not catalog-wide. Check provider, API, deployment, filtering, region, capacity, and tool support. [4]
gpt-5.5
gpt-5.4-mini
gpt-5.4-nano
The Voice Live overview lists these as tested through BYOM, not pre-deployed managed choices.Reuse a compatible deployment rather than assuming the model appears in the managed list.Direct Voice Live BYOM support must still be checked separately from native voice-agent deployment support. [5]

Speech recognition and synthesis: separate layers

Do not substitute a speech model name for the agent's conversation-model deployment.
LayerExamplesWhat matters for this customer
Speech recognitionazure-speech; supported whisper-1, gpt-4o-transcribe, and gpt-4o-mini-transcribe combinations.Evaluate names, business terms, accent coverage, noise, and corrections. Phrase lists and custom speech support depend on the selected recognizer and path. The compatibility matrix is not identical for all chat models. [6]
MAI transcription Previewmai-transcribe currently aliases mai-transcribe-2; mai-transcribe-2-streaming is a separate streaming choice.Streaming produces intermediate and final text while audio arrives. Test accuracy and turn latency separately. Voice Live's current guide documents the model IDs; native agent configuration exposure must be verified. Streaming has narrower regional availability than the non-streaming option. [6] [11] [12]
Azure speech outputStandard neural voices, HD voices, and eligible custom voices; compatible realtime models can use Azure TTS output.Choose the locale, pronunciation, speed, persona, and latency appropriate to the workflow. Broad Speech coverage does not imply every HD or custom voice works in every configuration. [5] [6]
MAI synthesis PreviewMAI-Voice-2.1-Flash
MAI-Voice-2.1
Flash targets low-latency interactive speech; the non-Flash model emphasizes expressive, high-fidelity, long-form output. Current documentation lists 23 languages and gated, consented voice cloning. Voice Live integration is explicitly documented for Flash; verify the exact voice-agent surface. [10]

Managed versus self-deployed is a hosting choice

managed uses a supported service-managed model name. self_deployed uses a compatible Foundry deployment name. This is separate from choosing native speech versus a cascaded pipeline.

Self-deployed does not mean the customer must host the voice agent. Reusing PTUs for the model also does not reserve the rest of the speech pipeline's capacity. [4]

Recommended first comparison Proposed

Compare a supported full realtime model with a mini realtime option. Add a text-model pipeline using the customer's existing agent/model if it is already working well.

Keep prompts, tools, audio, scenario, and concurrency consistent. Score structured-record accuracy and confirmation behavior alongside time to first audio and cost per completed task.

05 / Reference architecture

The voice layer does not own enterprise policy.

These are logical patterns, not deployment templates or a statement that every component is supported in every network mode. Choose a pattern to discuss who owns the conversation and where enforcement belongs.

Preview path

Native Foundry voice agent

Web / mobile or telephoneAuthorized user; clear listening state; transcript and corrections for browser UX.
Foundry voice agent + Voice LiveVersioned instructions, managed or compatible self-deployed model, audio settings, tools, and optional specialist agent.
Authorized knowledge + action APIsRetrieval with access controls; schema validation; approved write to a system of record.

The native agent owns the managed voice orchestration. A client-side function still needs client implementation. Service-side tools use the supported MCP/toolbox path. Phone channels need provider setup, permissions, and a selected release version. [4] [8]

Entra + least privilegeExplicit confirmationApplication Insights + evaluationsSeparate retention decision
Continuity path

Voice Live connected to an existing Foundry text agent

Customer client / session layerUser authentication, secure session establishment, audio playback, interruption handling.
Voice Live ↔ Foundry text agentSpeech recognition and synthesis around the existing text model, instructions, tools, and knowledge.
Existing business integrationsPreserve current logic and enforce access at retrieval and write APIs.

Useful when the demo already meets the business need. Instrument voice-specific stages separately; text-model traces alone do not explain audio and turn-detection delays. A native voice-agent evaluation can run alongside this path rather than replacing it immediately. [3]

Preserve working toolsCapture client overridesBenchmark against native agent
Application-owned path

Direct Voice Live model session

Customer applicationClient experience and a secure backend/session-init layer. Do not ship durable service keys to the browser.
Voice Live session + chosen modelApplication configures instructions, audio, tools, and supported session updates.
Application-owned tools and stateExecute calls, manage workflow state, enforce authorization, and capture operational telemetry.

Suitable for custom real-time interaction, but your application owns more lifecycle and integration work. Voice Live documents WebSocket and WebRTC paths; confirm the transport supported by the specific native agent or direct API surface rather than treating them as interchangeable. [6]

Session lifecycle in the appClient and backend telemetryNo implicit agent versioning

Enforcement boundary: the prompt guides behavior; the API and destination enforce identity, authorization, schema, confirmation, and irreversible writes. A spoken instruction such as "save this" must not bypass those controls.

06 / A reusable capture pilot

A leadership survey that starts with a brain dump.

Illustrative thin vertical slice: capture a natural response, understand which topics are already covered, ask only necessary questions, and produce an approved structured record. This is a design recommendation, not an out-of-the-box survey product.

Desired conversation Illustrative

UserOur team works well together, but reviews take too long. We need clearer ownership and better onboarding. Collaboration is probably a four out of five.
AgentI heard strong collaboration, slow reviews, and opportunities around ownership and onboarding. What would improve the review process most?
UserA single reviewer accountable for the final decision. And make that collaboration score a three, not a four.
AgentUpdated to three. Your recommendation is one accountable final reviewer. Please review the summary on screen before I save it.

No customer data or live model call is embedded in this guide. The dialogue is an authored test scenario.

Workflow that makes it reliable

  1. Listen without over-interrupting

    Let users cover several themes before imposing a form-like sequence.

  2. Maintain explicit coverage state

    Track covered fields, unanswered questions, contradictions, and user corrections.

  3. Generate a draft record

    Validate fields, ranges, required values, and provenance at an API boundary.

  4. Read back and display

    Let the user correct the interpretation in voice or text. Do not infer approval from silence.

  5. Commit only after confirmation

    Bind confirmation to the current draft and authenticated user. Use an idempotency key to prevent duplicate saves.

Example final record contract

{
  "schemaVersion": "1.0",
  "draftId": "example-draft-001",
  "collaborationScore": 3,
  "themes": [
    "review delays",
    "ownership",
    "onboarding"
  ],
  "recommendation": "One accountable final reviewer",
  "status": "awaiting_user_confirmation"
}

Keep the contract outside the prompt

A schema-shaped model response is still untrusted input. The backend should verify score range, allowed fields, record ownership, and the confirmation state before writing.

Derive user identity and audit metadata from trusted server context, not from spoken names or model-supplied JSON. A failed write must remain a failure; the agent must not announce that the record was saved.

Next reuse targets: client-preparation notes, coaching feedback, knowledge lookup, and later CRM or time-entry drafts, once the core capture-and-confirm pattern is proven.

07 / The likely demo-to-pilot blocker

"Publishing" is several different decisions.

A playground success is not the same as a browser experience, phone channel, Teams app, or production release. Define the destination before diagnosing the blocker. The current voice-specific Channels experience is not identical to text-agent publishing. [7]

DEVELOPER

Playground

Build and test with a microphone, transcript, and optional avatar. Proves a conversational path, not end-user distribution or production readiness.

CONTROLLED SHARING

Preview web app

The voice Channels tab can expose a browser preview when the endpoint supports the Responses protocol. Grant intended organizational users access and test with their accounts. A link is not authorization.

PHONE CALLS

Telephony

Teams Phone extensibility uses Azure Communication Services; Twilio uses a provider connection. Number ownership, licensing, identity, and inbound/outbound configuration still matter.

CUSTOM EXPERIENCE

Application

Build the web/mobile UX, authentication, session lifecycle, error handling, and deployment wrapper. Verify the supported native voice media path rather than assuming generic Agent Application guidance applies.

Teams Phone is not Teams app publishing. Connecting a Teams-owned number routes a telephone call through the supported telephony integration. It does not publish a conversational voice app into Teams or Microsoft 365 Copilot. The standard Teams/M365 publishing card is intentionally absent from the current voice Channels layout. [7]

Telephony prerequisites to surface early

  • Teams Phone: a service number/resource account, administrator involvement, ACS connection and consent; inbound routing includes Event Grid.
  • Twilio: an active voice-capable number for inbound use and a protected provider connection; no ACS or Event Grid requirement for that path.
  • Current Teams project-managed-identity integration requires the Foundry project and ACS resource to share a tenant.
  • Outbound calling uses the call-job API and provider connection; it is not simply the inbound number binding reversed.

Telephony details [8]

Release the version you tested

  1. Save an immutable agent version.
  2. Run browser and tool regression scenarios against that version.
  3. Test the actual preview link or telephone channel with a non-builder identity.
  4. Record the version, permissions, model/deployment, connections, and rollback target.
  5. Revalidate after model, guardrail, tool, audio, or channel changes.

Versioning [4] Release guidance [7]

08 / Operational and enterprise readiness

Optimize the whole turn, not just the model.

User-perceived latency includes end-of-turn detection, recognition where applicable, model inference, retrieval/tools, synthesis, networking, and playback. Some stages stream or overlap, so adding stage timings is only a diagnostic approximation. Time to first audio is the customer-facing metric. [4] [9]

Trace the voice pipeline

Connect the project's Application Insights and inspect the conversation/turn waterfall: VAD, speech-to-text where used, model calls, tool calls, and speech output. Voice traces use the common Foundry observability stack.

Review median and tail time to first audio, interrupted turns, tool errors, throttling, and completed-task rates. A fast model cannot hide a slow CRM API. [9]

Decide what gets stored

Conversation persistence is off by default. In the current voice definition, store: true persists the transcript, event timeline, and raw audio together; it is not a transcript-only switch.

Trace content capture is a separate setting. Apply notice, consent, retention, access, and download controls to both. Prefer approved structured records if raw audio is not needed. [4] [9]

Validate identity and locality

Separate the caller's identity, agent identity, tool identity, and human trace-reader permissions. Authorize every data operation and verify whether a tool acts as a user or an application.

A resource region does not prove all processing stays there. LLM inference, recognition, and HD synthesis can have different scopes. [7] [12]

Safety versus latency is an explicit trade-off. Asynchronous output filtering can reduce text buffering in supported configurations, but speech may be heard before a delayed policy signal arrives. Spoken content cannot be retracted. Keep required controls enabled; choose synchronous moderation if policy requires checks before any content is heard. [4]

Pilot acceptance tests Suggested targets, not Microsoft guarantees

Agree thresholds with the customer before the pilot. Run the same test pack across candidate architectures.
AreaTestProposed evidence / gate
Natural capture20 scripted and paraphrased survey conversations, including long pauses and multiple themes.At least 95% agreement with human-labeled required fields; report sample size and failure types.
CorrectionsChange a rating, negate a recommendation, interrupt a read-back, and resume.All correction cases update the draft; no stale values survive into the confirmed record.
Write safetyRefuse confirmation, repeat save requests, retry after a network failure, and attempt an unauthorized write.Zero unconfirmed, duplicate, or unauthorized writes in the test pack; failures are explicitly reported.
LatencyMeasure no-tool and tool-assisted turns independently at expected load.Suggested starting goal: no-tool p50 time to first audio ≤1.5 s and p95 ≤3 s, measured from end of user speech. Negotiate by channel; no product SLA implied.
InterruptionSpeak during agent playback on browser and selected phone path.Measure time to stop audible playback; suggested p95 ≤500 ms. No overlapping stale answer resumes incorrectly.
Security / operationsUse a recipient identity, revoked access, failed tools, and opted-out recording.Access denied where expected; no secrets in client; retention behavior verified; traces explain failures without unnecessary sensitive content.
Load / economicsRun at agreed concurrent-session load and record input, output, tools, and retries.Report p95 latency, throttles, task success, and cost per approved record; choose a capacity and spend ceiling before expansion.

Cost: measure a completed business outcome

Include all cost surfaces

  • Selected model hosting/inference path, audio and text usage, cached context, and growing conversation history.
  • Speech options, custom voice/speech training and hosting, and optional avatars.
  • Telephony/provider charges, application hosting, retrieval, tool execution, telemetry, and opted-in storage.

Direct Voice Live's Pro / Standard / Lite classification follows the model choice. Native-agent managed versus self-deployed billing needs its own validation; do not assume every path has the same meter. [3] [5]

No misleading dollar-per-minute quote

Regional pricing, agreements, model versions, talking ratios, output length, provider minutes, and tool calls change the total. Use actual pilot telemetry and the current pricing pages rather than a universal per-minute estimate.

Business metric: total measured pilot consumption divided by successfully approved records. Compare quality at that cost, not merely the price of one model token.

Current Azure Speech pricing [14]

09 / Model Mondays and research context

Use the episode as a demo companion, not an availability contract.

The supplied session, Voice Agents Upgraded: New Speech Models and Agent Experience In Foundry, is a useful conversation starter. The link begins at 56:48; that is the user-provided playback offset, not a verified chapter boundary.

Provided video

Watch with three questions in mind

  1. Which part is speech recognition, which is synthesis, and which is the conversation model?
  2. Which capabilities are configured in the agent versus implemented in the client or a tool?
  3. What is demonstrated, and what must still be validated for this tenant, region, channel, and network?
Source discipline

What this briefing treats as evidence

The video's transcript could not be retrieved. YouTube page/caption access and alternate public transcript routes did not yield usable captions. No transcript quotes, guest-speaker attributions, or chapter timestamps have been invented. Product claims are independently grounded in Microsoft documentation.

The official Model Mondays repository lists an October 12, 2026 speech-model session, Season 4 / Episode 9, hosted by Gustavo Cordido. Its written overview covers speech capabilities and responsive voice agents; it is supporting context, not a replacement for the video's captions. [17]

Current documentation can describe capabilities added after a recording. Newer model entries in this guide are labeled as current catalog examples rather than attributed to the episode.

Documentation-backed follow-up to the session's themes

New speech models

Explore the documented MAI transcription and synthesis families separately. Streaming transcription is not speech-to-speech reasoning; Flash synthesis is not an agent model. Verify availability at the intended integration surface. [10] [11]

Agent build experience

The current quickstart covers voice interaction mode, model selection, audio settings, tools, knowledge, and browser testing. A saved voice agent can be developed through portal or supported SDK/CLI workflows. [2]

Operations beyond the demo

Follow up with native voice-pipeline tracing, the voice-specific Channels documentation, and migration guidance. These details decide whether a preview meets the customer's deployment needs. [3] [7] [9]

10 / Run the customer call

Leave with a decision, not another broad overview.

Suggested opening: Let us see what is working, identify precisely what is blocking sharing or release, and compare that with the new native voice-agent path. We should leave with one pilot, a clear architecture choice, and owners for the remaining validations.

A focused 30-minute agenda

Demo first. Identify current architecture, client, successful scenarios, and the exact meaning of publishing.
Architecture fit. Compare voice-native and existing text-agent paths; agree model tests, tools, knowledge, and target channel.
Trust boundaries. Confirm user/tool identities, retention, networking, write confirmation, and preview acceptance.
Choose the pilot. Agree the leadership-survey slice, destination schema, test pack, latency goals, and spend ceiling.
Name owners. Record architecture, release target, blockers, rollback, and the next checkpoint.

Decision checklist

Optional in-page meeting aid. Checkmarks stay only in this open page; no data is saved or sent.

0 of 8 decisions checked.

Questions worth answering explicitly

Should the customer rebuild the current demo?
No automatic rebuild is recommended. Benchmark the working architecture against a separate native voice agent. Migrate only if managed voice configuration, speech-to-speech, built-in channels, or operations provide a material advantage and the preview constraints are acceptable. [3]
Does choosing Foundry voice agents require a realtime model?
No. The new agent type supports supported realtime and text-model paths. Native speech versus cascaded architecture is distinct from service-managed versus self-deployed model hosting. [4]
Can the agent retain context and avoid repeated survey questions?
Within a conversation, model context and explicit workflow state can track covered topics. Reliable field completion, corrections, reconnects, and cross-session continuity need application/state design and tests. Conversation storage is not by itself a memory strategy.
Can we keep everything private or in one region?
Do not infer that from generic Foundry support. Validate the exact preview, model deployment, speech processing scopes, tools, and transport. Voice subagents are explicitly unsupported in VNet-isolated projects. Data-zone inference can span regions within a zone; it is not a regional pin. [4] [12] [13]
Can we simply attach a tool and let it save to CRM or SharePoint?
The tool/API must enforce authorization, validate the payload, bind confirmation to the current draft, and handle retries safely. Prefer a draft-and-confirm pilot before broad write access. Do not treat spoken user identity, retrieved content, or model output as trusted authorization.
What should be escalated to the Microsoft product team?
Escalate a concrete unsupported combination, not a generic request to publish: agent type/version, target region, model/deployment, channel, network mode, transport, sanitized error, and reproduction steps. Never include credentials or raw customer recordings in an ordinary support artifact.
11 / Evidence and further reading

Source register

Official Microsoft documentation is the authority for product behavior. Recommendations, example dialogue, architecture sketches, and pilot targets are illustrative, independently authored guidance, not customer deployment evidence.

Research boundary: checked October 16, 2026 against the public pages linked above. No Azure tenant, subscription, model capacity, pricing agreement, or customer deployment was inspected. Availability and preview terms can change. Use this guide for the discussion, then validate the selected combination in the intended project.