> ## Documentation Index > Fetch the complete documentation index at: https://docs.miraiminds.co/llms.txt > Use this file to discover all available pages before exploring further. # Validate a flow > Checks a graph against every rule without saving it: node and transition counts, ids and labels, that every node can be reached and can reach an end, and that your tier's model can run flows. Free, and it calls no one. The body is the graph itself. Every problem comes back at once, each with the path to the field. Whether the graph's variables and node tools exist on a particular agent is checked when you save it on that agent. ## OpenAPI ````yaml /api-reference/openapi.json post /v2/agents/flow/validate openapi: 3.1.0 info: title: Mirai Voice API version: 2026-10-15.analysis-templates description: >- The v2 API for voice agents, calls, campaigns, phone numbers and speech. Every request carries `Authorization: Bearer sk_live_…`. Generated from the API's own contract and its Postman collection. servers: - url: https://sandbox.voice.miraiminds.co description: 'Sandbox: trial workspaces, before your company goes live' - url: https://prod.voice.miraiminds.co description: 'Production: workspaces that have gone live' security: - bearerAuth: [] tags: - name: Agents description: >- An agent is what a call runs: its prompt (or a node flow, see the Flows section), voice, language and limits. Write it once and dial it as often as you like; each call fills in its own `variables`. Every save creates a new revision. You can read old revisions, roll back to one, and publish a draft when it is ready. None of the requests here place a call or charge your wallet. - name: Calls description: >- Place a call, follow it while it runs, then read what happened: the transcript, the recording, the post-call analysis. `POST /v2/calls` answers before the phone rings, with an id. Everything after that is about that id. Live control and the live event stream work on browser calls (`channel: "web"`) and realtime sessions only; a phone call answers them with `400 unsupported_channel`. - name: Flows description: >- A node-based agent runs the call as a graph of steps. Each node has its own instructions, and the agent moves to the next node when a transition's condition is met, so a call with branches (wrong person, not now, reschedule) stays easy to follow and to change. The usual path: draft a graph from a brief or from recordings of your real calls, check it, test it with simulated calls, then save it on an agent. Drafting, transcribing and testing use AI models and charge your wallet; checking, saving and reading are free. Full guide: https://docs.miraiminds.co/v2/node-agents - name: Tools and secrets description: >- Connect your own APIs to an agent. A tool runs at one of three moments: * `pre_call`, before dialling: fetch context for the greeting, or skip the call. * `on_call`, when the agent decides to use it mid-conversation: look something up, book something. * `post_call`, after the call has settled: send the outcome to your CRM, schedule a call back. The order here is the order you'd use them in: see what's available, store your credential as a secret, add a tool, test it against your endpoint, then read each call's tool runs. Tools themselves cost nothing extra. Tool definitions use Mirai's own templates, like `{{ args.date }}` and `{{ secrets.crm_key }}`. A definition that doesn't validate comes back as a list, so you can fix everything at once: `{"error": "invalid_tools", "details": [{"path", "message"}]}`. Everything else uses the usual `{"error": {"code", "message"}}`. - name: Campaigns description: >- Call a whole list with one agent. Upload contacts, say which days and hours the campaign may ring, and start it. From then on it dials by itself: it paces itself, waits overnight, retries calls that didn't connect, skips numbers on your do-not-call list, and pauses itself when its budget or your wallet runs out. Campaign calls are ordinary calls. They show up in `GET /v2/calls`, send the same `call.*` webhooks and bill the same per-minute rate. In a sandbox workspace every campaign runs and bills at T5 (₹5 a minute), whatever tier you ask for. Money on a campaign is in **paise**: `"budget_paise": 50000` is ₹500. The requests run top to bottom: create saves `campaign_id`, and the rest use it. Starting a campaign rings every contact on it, so put numbers you're allowed to call in the bodies first. - name: Do-not-call list description: >- Numbers your campaigns will never dial. The list covers every campaign in the workspace, including ones that are already running: it's checked at the moment a contact is about to be called, so a number added mid-campaign is skipped from then on. A skipped contact stays in its campaign as `suppressed` and costs nothing. It doesn't apply to single calls placed with `POST /v2/calls`; check the list yourself before those if you need to. It's your own list, not the national DND register, and adding a number here doesn't meet your DND obligations. - name: Phone numbers description: >- The numbers your agents answer. Each one comes from the **Telephony** section: * **Rented from Mirai.** Once the rental is active, the number shows up here by itself (`ownership: managed`). * **From your own Plivo account.** Connect the account in Telephony, list its numbers, then bring one here with [Import a Plivo number](/api-reference/phone-numbers/import-a-plivo-number) (`ownership: customer`). Plivo keeps billing you for it. After that it's two steps, in this order: [Assign an agent](/api-reference/phone-numbers/assign-an-agent) (who answers), then [Turn on incoming calls](/api-reference/phone-numbers/turn-on-incoming-calls). `state` is `imported` until calls are on and `ready` after; `error` means the last attempt to turn calls on failed, and `setup_error` says why. Every change sends the number's current `version`, and each change raises it by one. If you're not sure what it is, read the number first; a stale version is a 409 `conflict` and changes nothing. To call out from one of your numbers, place a call with `phone_number_id` set to its id once it is `ready` (Indian destinations only). Calls on your numbers are billed like any other call. Every number also says how it is doing in `health`: `state` is `active`, `warming` (its first week, at half its pool's pace), `resting`, `cooling` (rested three times in a day; waits for you) or `retired`, with this hour's attempts and seven days of answers. You can rest, resume and retire your own numbers; a resting or retired number still answers calls to it. - name: Phone pools description: >- A pool is a group of your own phone numbers that a campaign, an agent or a single call can ring from. Each call takes the number best placed for it: a number a contact has already been rung from stays theirs on a retry, numbers in the contact's own circle come first, and the pool's pace (`max_per_hour`, per number) is held across every campaign and API call at once. A number whose answers drop well below its pool-mates' rests on its own for 45 minutes. Point a campaign at a pool with `pool_id` on [Create a campaign](/api-reference/campaigns/create-a-campaign), an agent with `calls_from: {"pool_id": …}`, or one call with `pool_id` on [Place a call](/api-reference/calls/place-a-call). `pool_id` and `phone_number_id` never go together. With nothing chosen, calls come from the agent's setting, then the pool marked `default_for_campaigns`, then the Mirai shared line. A call's `calls_from_source` is `pool` (with `pool_id`) when a pool picked its number. A single call on a pool whose numbers are all resting or at their pace this hour answers 409 `pool_busy` with `Retry-After`; one with no number that can call, 409 `pool_unavailable`. A campaign doesn't fail: it waits and carries on. `purpose` is what the calls are for: `outreach` (promotional), `reminders`, `support` or `other`. It sets the starting pace: 40 an hour for support, 60 otherwise. Pools are free; numbers are billed as numbers. - name: Telephony description: >- Getting a phone number for your agent. There are two ways, and a workspace can use both. **1. Rent a number from Mirai.** ₹500 a month, paid as ₹1,500 from your wallet every three months, renewing until you turn it off. Indian numbers need a business verification that Plivo approves once: read the requirements, submit your details and documents, then refresh until it's `accepted`. After that: search, quote, rent. The rented number appears in **Phone numbers** by itself. **2. Connect your own Plivo account.** Plivo keeps billing you directly. Connect it with your Auth ID and Auth Token, list the numbers it owns, and bring one over with [Import a Plivo number](/api-reference/phone-numbers/import-a-plivo-number). A Plivo main account can also rent new numbers through the same search → quote → rent requests, with its connection id as `account`. Either way you finish in **Phone numbers**: assign the agent that answers, then turn on incoming calls. The last two requests verify your own phone, so the workspace can ring it from Mirai's shared test number (test calls are placed from the Numbers page in the console). Indian (+91) numbers only for now. If phone numbers aren't available on the host you're calling, every request here answers 503 `telephony_unavailable`. - name: Transcriptions description: >- Turn a recorded call (or any recording) into a transcript with speakers and timestamps. Hindi, English, Gujarati and mixed speech are written the way they were spoken, never translated. ₹18 per hour of audio; failed and degraded jobs are free. - name: Speech to text description: >- Speech to text in ten languages, two ways: send one recording and get its text back in the same request ([Transcribe a recording](/api-reference/speech-to-text/transcribe-a-recording)), or stream live audio over one WebSocket per call and read partial transcripts while people speak, then one final transcript per utterance. Language codes: hi-IN, en-IN, gu-IN, mr-IN, pa-IN, bn-IN, ta-IN, te-IN, kn-IN or ml-IN. `wss://sandbox.voice.miraiminds.co/v1/audio/transcriptions/stream?language_code=hi-IN&encoding=mulaw&sample_rate=8000&endpointing=manual` (`wss://prod.voice.miraiminds.co` once your company has gone live), with the header `Authorization: Bearer sk_live_YOUR_API_KEY`. 8 or 16 kHz, 16-bit PCM, μ-law or A-law. A browser uses `?token=` from [Mint stream tokens](/api-reference/speech-to-text/mint-stream-tokens) instead, because it cannot set headers on a WebSocket. Send JSON text frames: `{"event": "speech_start"}`, then `{"event": "audio_input", "audio": ""}` as the audio arrives, then `{"event": "speech_end"}`; `{"event": "end"}` closes the session. You receive `session.begin` first, `transcript.partial` while an utterance is open, exactly one `transcript.final` per utterance, and `session.end` with `audio_seconds_billed` and `cost_paise`. Every event, both endpointing modes, limits and errors: https://docs.miraiminds.co/v2/stt-quickstart - name: Text to speech description: >- Turn text into speech in one request, and read back what each request cost. - name: Wallet description: >- Your prepaid balance and every line that moved it. Calls, text to speech, flow drafts, transcriptions and number rentals all debit the same wallet. - name: Reference description: The voice catalogue, and the API contract as a machine-readable document. paths: /v2/agents/flow/validate: post: tags: - Flows summary: Validate a flow description: >- Checks a graph against every rule without saving it: node and transition counts, ids and labels, that every node can be reached and can reach an end, and that your tier's model can run flows. Free, and it calls no one. The body is the graph itself. Every problem comes back at once, each with the path to the field. Whether the graph's variables and node tools exist on a particular agent is checked when you save it on that agent. operationId: validate_agent_flow requestBody: required: true content: application/json: schema: additionalProperties: false description: >- A node graph: the conversation as nodes with their own instructions and transitions between them. See x-semantics.flow for the rules. properties: edges: items: $ref: '#/components/schemas/FlowEdge' maxItems: 40 minItems: 1 type: array nodes: items: $ref: '#/components/schemas/FlowNode' maxItems: 20 minItems: 2 type: array viewport: description: Editor camera. Any JSON; stored and returned as sent. required: - nodes - edges type: object x-max-bytes: 100000 examples: Validate a flow: summary: Validate a flow value: nodes: - id: persona type: globalNode data: name: Persona and rules prompt: >- You are Ashu, a service advisor at Mirai Motors. Speak everyday Hindi in Devanagari; common English words such as service, slot and workshop are fine. Say one or two short sentences, then listen. Never promise a discount, a price or a pickup. When the condition of one of your functions is met, call it at once without saying anything first. - id: identity type: startCall data: name: Confirm the customer greeting: >- नमस्ते, मैं मिराई मोटर्स से आशु बोल रहा हूं. क्या मेरी बात {{name}} जी से हो रही है? prompt: >- You have asked whether you are speaking with {{name}}. Wait for the answer. If they confirm, call confirmed_identity. If it is someone else or a wrong number, call wrong_person. Do not mention the car or the service before they confirm. - id: offer_slot type: agentNode data: name: Book the service prompt: >- Tell them their {{vehicle}} is due for service on {{due_date}}, and ask which day they can bring it to the workshop. When they name a day, read it back once and call slot_booked. If they do not want to book now, call not_now. extraction_enabled: true extraction_variables: - name: preferred_day type: string prompt: >- The day the customer chose for the service, in their words, for example Saturday or 20 August. - id: goodbye type: endCall data: name: Close prompt: >- In one sentence, repeat what was agreed. Thank them and say goodbye. Do not ask anything else. allow_interrupt: false - id: not_customer type: endCall data: name: Wrong person prompt: >- Apologise for the trouble and say goodbye. Do not mention the car or the service. edges: - id: e1 source: identity target: offer_slot data: label: confirmed_identity condition: >- The caller confirmed they are the customer you asked for. - id: e2 source: identity target: not_customer data: label: wrong_person condition: >- The caller is someone else, or says it is a wrong number. - id: e3 source: offer_slot target: goodbye data: label: slot_booked condition: >- The customer named a day for the service and you read it back. - id: e4 source: offer_slot target: goodbye data: label: not_now condition: The customer does not want to book the service now. responses: '200': description: Valid content: application/json: schema: $ref: '#/components/schemas/FlowValidation' examples: Valid: summary: 200 — valid value: edges: 4 flow_revision: 2c0eccdffdf0edca4e0a nodes: 5 ok: true '400': description: Every problem, with its path content: application/json: examples: Every problem, with its path: summary: 400 — every problem, with its path value: details: - path: flow.edges[2].data.label message: >- must be a function name: a letter or underscore, then letters, digits or underscores (at most 64) - path: flow.edges[3].data.condition message: >- is required: describe when the model should take this transition error: invalid_flow components: schemas: FlowEdge: additionalProperties: false properties: animated: description: Editor field. Any JSON; stored and returned as sent. data: additionalProperties: false properties: condition: description: >- When to take it; given to the model as the function's description. Must not be blank. maxLength: 2000 minLength: 1 type: string label: description: >- The function name the model calls to take this transition. Unique among the source node's transitions. pattern: ^[a-zA-Z_][a-zA-Z0-9_]{0,63}$ type: string required: - label - condition type: object id: description: Unique in the graph. minLength: 1 type: string source: description: A node id; not an endCall or the globalNode. type: string target: description: A node id; not the globalNode. type: string type: description: Editor field. Any JSON; stored and returned as sent. required: - id - source - target - data type: object FlowNode: additionalProperties: false properties: data: $ref: '#/components/schemas/FlowNodeData' id: description: Unique in the graph. pattern: ^[a-zA-Z_][a-zA-Z0-9_]{0,63}$ type: string position: description: Editor layout. Any JSON; stored and returned as sent. type: description: >- startCall opens the call (exactly one); endCall ends it after its reply (at least one, no outgoing transitions); globalNode is a prompt prepended to every node with add_global_prompt (at most one, no transitions). enum: - startCall - agentNode - endCall - globalNode type: string required: - id - type - data type: object FlowValidation: properties: edges: type: integer flow_revision: type: string nodes: type: integer ok: const: true type: object FlowNodeData: additionalProperties: false properties: add_global_prompt: default: true type: boolean allow_interrupt: default: true type: boolean extraction_enabled: default: false type: boolean extraction_variables: default: [] items: $ref: '#/components/schemas/FlowVariable' maxItems: 12 type: array greeting: description: >- Exact line spoken on entering the node; the start node's greeting opens the call. maxLength: 1500 type: - string - 'null' is_start: description: Derived from type on save. type: boolean name: maxLength: 80 minLength: 1 type: string prompt: description: >- The node's instructions, including when to call each outgoing transition. {{variables}} are rendered per call. maxLength: 12000 minLength: 1 type: string tools: description: >- Names of this agent's on_call tools the node offers the model beside its transitions, in order. startCall and agentNode only; never end_call and never a transition label. Omitted when empty. items: pattern: ^[a-zA-Z_][a-zA-Z0-9_]{0,63}$ type: string maxItems: 10 type: - array - 'null' uniqueItems: true required: - name - prompt type: object FlowVariable: additionalProperties: false properties: name: description: Unique within the node. pattern: ^[a-zA-Z_][a-zA-Z0-9_]{0,63}$ type: string prompt: maxLength: 2000 minLength: 1 type: string type: enum: - string - number - boolean type: string required: - name - type - prompt type: object securitySchemes: bearerAuth: type: http scheme: bearer description: >- Your workspace secret key, `sk_live_` followed by 32 hex characters. Create one in the console under **Developers**. ```` This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.