> ## Documentation Index > Fetch the complete documentation index at: https://docs.mcpjam.com/llms.txt > Use this file to discover all available pages before exploring further. # Launch a journey > Answers **202**: the run row exists and its fan-out has started. It is not finished — poll `GET /projects/{projectId}/journey-runs/{runId}` until `status` leaves `running`. **SPENDS.** A launch fans out into `targets × sessionsPerTarget` chat sessions, every one of which runs a model on your organization's account. Two different 429s can come back and they mean different waits: the per-minute burst brake (retry in seconds) and your plan's daily launch cap (resets at UTC midnight). Both normally carry `Retry-After` — honor it when it is there, and back off on your own when it is not, rather than blocking on a header that may not come. A retried `Idempotency-Key` consumes NO quota. ## OpenAPI ````yaml /reference/openapi.json post /projects/{projectId}/journeys/{journeyId}/runs openapi: 3.1.0 info: title: MCPJam API version: 1.0.0-preview description: >- Programmatic access to MCP servers saved in your MCPJam projects — live diagnostics (validate, inspect, export) and operations: call tools, render prompts, run eval suites asynchronously and poll their results, and import OAuth tokens. **The API is in preview**: the surface may change while we finish the design. Error `code` values are stable; error `message` strings are not. Write clients that ignore unknown response fields. contact: name: MCPJam url: https://github.com/MCPJam/inspector/issues servers: - url: https://app.mcpjam.com/api/v1 description: Hosted MCPJam security: - bearerAuth: [] tags: - name: Hosts description: >- Project hosts: named model + capability profiles you run chats and eval suites against. - name: Environments description: >- Project environments: named, live-editable execution bundles (one host, an optional standalone server group, optionally pinned skills and plugin versions) that eval suites and journeys run against. Distinct from Sandbox images, which are Computer base images. Reads require project membership; every write requires project admin. - name: Plugins description: >- Agent Plugins imported into a project — read-only inventory and version detail. - name: Sandbox images description: >- Custom Computer images: a digest-pinned Dockerfile built into an immutable image your project's computers boot from. - name: Server diagnostics description: Connect-level health checks against a saved MCP server. - name: Primitives description: 'The server''s MCP primitives: tools, prompts, and resources.' - name: Export description: Full-server snapshots for diffing and CI. - name: Execution description: 'Run the server''s primitives: call tools, render prompts.' - name: Eval runs description: >- Asynchronous eval suite runs: create with 202, poll status, iterations, and traces. - name: Server connections description: >- Connect an MCP server URL to a project, authorizing in a browser when the server requires it. - name: OAuth description: 'Bring-your-own OAuth: import externally obtained tokens for a server.' - name: Chatboxes description: >- Read-only access to the chatboxes published from a project: listing, settings, attached servers, and share links. - name: Catalog description: >- Discover the resources the other routes operate on: your account, projects, servers, eval suites, and chat sessions. - name: Tunnels description: >- Relay tunnels that expose local MCP servers through a public URL, registered as first-class project servers (the `mcpjam tunnel` CLI flow). - name: Agent description: >- Headless agent turns over the public API: send a message history, the server runs one assistant turn with project-scoped workspace tools (eval reads + suite creation) on a pinned hosted model, and returns the reply plus created-resource references. - name: Swarms description: >- Personas, journeys and swarm containers — the authoring half of Swarms — plus the model-backed generation that drafts them. - name: Swarm runs description: >- Launching journeys and reading what they produced. Launching SPENDS — see the per-operation notes. - name: Swarm insights description: >- What a swarm run revealed. The scorecard and findings are deterministic and free; requesting wave insights runs models and draws on your shared daily ledger. - name: User testing description: >- Publishing an environment for real visitors, and controlling who can reach it. Several of these NARROW access and take effect immediately. paths: /projects/{projectId}/journeys/{journeyId}/runs: parameters: - $ref: '#/components/parameters/projectId' - $ref: '#/components/parameters/journeyId' post: tags: - Swarm runs summary: Launch a journey description: >- Answers **202**: the run row exists and its fan-out has started. It is not finished — poll `GET /projects/{projectId}/journey-runs/{runId}` until `status` leaves `running`. **SPENDS.** A launch fans out into `targets × sessionsPerTarget` chat sessions, every one of which runs a model on your organization's account. Two different 429s can come back and they mean different waits: the per-minute burst brake (retry in seconds) and your plan's daily launch cap (resets at UTC midnight). Both normally carry `Retry-After` — honor it when it is there, and back off on your own when it is not, rather than blocking on a header that may not come. A retried `Idempotency-Key` consumes NO quota. operationId: launchJourneyRun parameters: - name: Idempotency-Key in: header required: false description: >- **Send one.** A launch spends model credits, so a retry of a dropped response must not run the journey twice. Replaying a key returns the ORIGINAL run with `deduped: true` and starts no second runner. Omitting the header is read as a request that declined to identify itself, and gets a FRESH run every time. schema: type: string requestBody: required: false description: >- Optional launch options. Omit the body entirely to run the journey as authored. content: application/json: schema: $ref: '#/components/schemas/JourneyRunLaunchRequest' responses: '202': description: The run was accepted and started. content: application/json: schema: $ref: '#/components/schemas/JourneyRunLaunched' '400': $ref: '#/components/responses/ValidationError' '401': $ref: '#/components/responses/Unauthorized' '403': $ref: '#/components/responses/Forbidden' '404': $ref: '#/components/responses/NotFound' '409': $ref: '#/components/responses/Conflict' '429': $ref: '#/components/responses/RateLimited' '500': $ref: '#/components/responses/InternalError' components: parameters: projectId: name: projectId in: path required: true description: ID of the hosted project that contains the server. schema: type: string journeyId: name: journeyId in: path required: true description: Journey ID, as returned by the project's journey list. schema: type: string schemas: JourneyRunLaunchRequest: type: object description: >- Optional. A launch with no options is a BODYLESS POST — omit the body entirely rather than sending `null`, which is rejected. additionalProperties: false properties: waveId: type: string maxLength: 64 description: >- Opaque id linking the sibling runs of one co-launched batch. Mint it yourself and reuse it across the launches you want grouped. environmentIds: type: array items: type: string minItems: 1 description: >- Fan out across THESE environments instead of the journey's authored targets. NON-EMPTY when present: `[]` is a caller saying "across these" while naming none, and would have silently launched the authored targets instead. Silently running something other than what was asked for is bad anywhere; on an operation that spends it is worse. Omit the field to mean "as authored". JourneyRunLaunched: type: object required: - id - journeyId - projectId - status - deduped properties: id: type: string description: The run id. Poll it, or stop it with `cancel`. journeyId: type: string projectId: type: string status: type: string description: >- Always `running` — the run row exists and its fan-out has started. This is a 202: nothing here says the journey has finished, only that it is under way. enum: - running deduped: type: boolean description: >- True when an `Idempotency-Key` replayed onto a run that ALREADY existed, so nothing new was started. The response is otherwise identical, which is how a retry of a dropped request tells "I launched it" from "it was already going" without a second read. Error: type: object required: - code - message properties: code: type: string description: >- Stable, machine-readable error code. New codes may be added over time; treat unknown codes as non-retryable failures unless the HTTP status says otherwise. enum: - UNAUTHORIZED - FORBIDDEN - NOT_FOUND - CONFLICT - VALIDATION_ERROR - RATE_LIMITED - FEATURE_NOT_SUPPORTED - SERVER_UNREACHABLE - TIMEOUT - OAUTH_REQUIRED - INTERNAL_ERROR message: type: string description: >- Human-readable description. May change between releases — don't match on it. details: type: object description: Optional, unstructured context bag. additionalProperties: true responses: ValidationError: description: Malformed body or parameters. content: application/json: schema: $ref: '#/components/schemas/Error' example: code: VALIDATION_ERROR message: Invalid JSON body Unauthorized: description: >- Missing, invalid, revoked, or orphaned key (`UNAUTHORIZED`) — or the **target MCP server** needs an OAuth grant (`OAUTH_REQUIRED`), which is a property of the server, not your key. content: application/json: schema: $ref: '#/components/schemas/Error' examples: badKey: summary: Invalid or revoked key value: code: UNAUTHORIZED message: Invalid API key oauthRequired: summary: Target server needs an OAuth grant value: code: OAUTH_REQUIRED message: Server requires OAuth authorization Forbidden: description: Key is valid but not allowed to do this. content: application/json: schema: $ref: '#/components/schemas/Error' example: code: FORBIDDEN message: You do not have access to this project NotFound: description: Unknown project, server, or resource. content: application/json: schema: $ref: '#/components/schemas/Error' example: code: NOT_FOUND message: Server not found Conflict: description: >- The resource is not in a state that accepts this write — a stale `expectedRevision`, a duplicate name, or an environment that cannot currently be launched. The request was well-formed; re-read the resource and retry. content: application/json: schema: $ref: '#/components/schemas/Error' example: code: CONFLICT message: >- Environment changed since you loaded it (expected revision 3, current 5). Reload and retry. RateLimited: description: >- Per-key rate limit exceeded (60 requests/minute sustained, bursts up to 10). Honor `Retry-After` and back off with jitter. headers: Retry-After: description: Seconds to wait before retrying. schema: type: integer content: application/json: schema: $ref: '#/components/schemas/Error' example: code: RATE_LIMITED message: API key rate limit exceeded. Slow down and retry. InternalError: description: Something failed on MCPJam's side. content: application/json: schema: $ref: '#/components/schemas/Error' example: code: INTERNAL_ERROR message: Unexpected internal error securitySchemes: bearerAuth: type: http scheme: bearer description: >- MCPJam API key (`sk_…`). Create one at [Settings → API keys](https://app.mcpjam.com/settings/api-keys). Guest sessions cannot use the API, and API keys cannot manage other API keys. ````