> ## Documentation Index > Fetch the complete documentation index at: https://docs.getcliq.io/llms.txt > Use this file to discover all available pages before exploring further. # Send a task to a realm > JSON-RPC 2.0 endpoint for A2A clients, with the realm's A2A token: `message/send` starts a task (a run of the skill's team; name the skill in `message.metadata.skill_id` or a data part, with `inputs`) and returns it; `message/stream` does the same and streams status updates as server-sent events until the task ends; `tasks/get` returns a task by `id`. JSON-RPC errors (unknown method, missing `id`) come back as `{ jsonrpc, id, error: { code, message } }` with HTTP 400. Requires the realm's A2A bearer token (`Authorization: Bearer cliq_a2a_…`), minted with Generate a token (`type: "a2a"`). ## OpenAPI ````yaml /openapi/hub-by-tag/hub-a2a.yaml post /a2a/o/{org}/r/{slug}/send openapi: 3.0.3 info: title: 'CliqHub API: A2A' version: 1.0.0 description: >- Agent-to-agent (A2A) access to a realm. Outside agents read the realm's agent card to see its skills (one per team the realm runs), then send tasks with JSON-RPC to `send`, using the realm's A2A token. A2A must be turned on for the realm (Realms, Manage A2A for a realm). servers: - url: https://{host} variables: host: default: cliqhub.io description: CliqHub host security: [] tags: - name: A2A description: >- Agent-to-agent (A2A) access to a realm. Outside agents read the realm's agent card to see its skills (one per team the realm runs), then send tasks with JSON-RPC to `send`, using the realm's A2A token. A2A must be turned on for the realm (Realms, Manage A2A for a realm). paths: /a2a/o/{org}/r/{slug}/send: post: tags: - A2A summary: Send a task to a realm description: >- JSON-RPC 2.0 endpoint for A2A clients, with the realm's A2A token: `message/send` starts a task (a run of the skill's team; name the skill in `message.metadata.skill_id` or a data part, with `inputs`) and returns it; `message/stream` does the same and streams status updates as server-sent events until the task ends; `tasks/get` returns a task by `id`. JSON-RPC errors (unknown method, missing `id`) come back as `{ jsonrpc, id, error: { code, message } }` with HTTP 400. Requires the realm's A2A bearer token (`Authorization: Bearer cliq_a2a_…`), minted with Generate a token (`type: "a2a"`). operationId: POST_a2a_o_org_r_slug_send parameters: - name: org in: path required: true schema: type: string description: The organization's slug. - name: slug in: path required: true schema: type: string description: The realm's slug. requestBody: required: true content: application/json: schema: type: object properties: jsonrpc: type: string enum: - '2.0' description: Always `2.0`. id: oneOf: - type: string - type: number - description: Unsupported Zod expression `z.null()` type: object additionalProperties: true description: Your request id, echoed in the response. method: type: string minLength: 1 description: '`message/send`, `message/stream` or `tasks/get`.' params: type: object additionalProperties: true description: >- The method's parameters: `message` for send and stream, `id` for `tasks/get`. required: - method examples: send: summary: Start a task value: jsonrpc: '2.0' id: 1 method: message/send params: message: role: user parts: - kind: text text: Review PR 42 metadata: skill_id: acme/code-review inputs: pr_url: https://github.com/acme/api/pull/42 responses: '200': description: >- A JSON-RPC response `{ jsonrpc, id, result }` whose `result` is the task (for `message/stream`, a `text/event-stream` of such messages). content: application/json: schema: type: object properties: ok: type: boolean enum: - true description: Always `true` on success. jsonrpc: type: string enum: - '2.0' id: description: The request's id. result: type: object properties: id: type: string description: Task id. contextId: type: string status: type: object properties: state: type: string enum: - submitted - working - completed - failed - canceled message: type: string metadata: type: object properties: realm_id: type: string skill_id: type: string queue_item_id: type: string run_id: type: string nullable: true artifacts: type: array items: type: object additionalProperties: true required: - ok example: ok: true jsonrpc: '2.0' id: 1 result: id: 9c0d1e2f-3a4b-4c5d-8e6f-7a8b9c0d1e2f status: state: submitted metadata: realm_id: 5b0c3a7e-2f4d-4b8e-9a51-7c1d2e3f4a5b skill_id: acme/code-review queue_item_id: e1d2c3b4-a5f6-4789-8a0b-1c2d3e4f5a6b run_id: null '400': description: >- `bad_request`: `message/send` or `message/stream` without a skill id, or the body is not JSON-RPC (no `method`). content: application/json: schema: $ref: '#/components/schemas/HubErr' examples: bad_request: summary: bad_request value: ok: false error: skill_id required (message.metadata.skill_id or data part) code: bad_request '401': description: >- `unauthorized`: The A2A bearer token is missing, wrong, or A2A is turned off for the realm. `unauthorized`: No `Authorization` bearer, or it is not the realm's A2A token. content: application/json: schema: $ref: '#/components/schemas/HubErr' examples: unauthorized: summary: unauthorized value: ok: false error: code: unauthorized message: Authentication required unauthorized (endpoint): summary: unauthorized (endpoint) value: ok: false error: Bearer does not match realm code: unauthorized '403': description: '`forbidden`: A2A is turned off for the realm.' content: application/json: schema: $ref: '#/components/schemas/HubErr' examples: forbidden: summary: forbidden value: ok: false error: A2A is disabled for this realm code: forbidden '404': description: '`not_found`: No realm has this slug in the organization.' content: application/json: schema: $ref: '#/components/schemas/HubErr' examples: not_found: summary: not_found value: ok: false error: Realm 'production' not found code: not_found '422': description: >- `invalid_params`: The body fails the request schema: a required field is missing or a value has the wrong type or format. The message lists every issue as `field: problem`. content: application/json: schema: $ref: '#/components/schemas/HubErr' examples: invalid_params: summary: invalid_params value: ok: false error: 'method: Required' code: invalid_params '500': description: >- `internal_error`: An unexpected server fault. Retry later; if it persists, report it with the time of the request. content: application/json: schema: $ref: '#/components/schemas/HubErr' examples: internal_error: summary: internal_error value: ok: false error: Internal server error code: internal_error security: - A2aBearer: [] components: schemas: HubErr: type: object required: - ok - error description: >- Every failure. Route-policy denials (401/403/404, and 400 when neither realm_id nor org_id was sent) answer `error` as `{ code, message }`; errors raised by the endpoint answer `error` as the message with the code beside it in `code`. Every error has a code. See [Errors](/hub-api/errors). properties: ok: type: boolean description: Always false on error error: description: The message, or `{ code, message }` for an access denial. oneOf: - type: string - type: object required: - code - message properties: code: type: string message: type: string code: type: string description: Stable error code of an endpoint error. details: type: object additionalProperties: true description: Structured detail, when there is some. securitySchemes: A2aBearer: type: http scheme: bearer description: >- Realm A2A bearer (mint/rotate via /v1/auth/generate_token|rotate_token with type: a2a and realm_id). ```` This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.