> ## 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. # Read a chat session's messages > Session metadata plus a bounded window of its raw messages. `index` on each message is its ABSOLUTE position in the stored transcript, not its position in the returned page: trace spans reference messages positionally, so this read and `/trace` join on that number. A transcript that could not be read reports `transcriptUnavailable: true` and a **null** `messageCount` — never 0, which would claim the conversation is empty. ## OpenAPI ````yaml /reference/openapi.json get /chat-sessions/{sessionId} 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: Conformance runs description: >- Ingest MCP spec-conformance results from the SDK/CLI into project-owned history. Distinct from Eval runs (authored LLM cases) and from directory readiness. - 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: Scenarios description: >- Read-only access to the scenarios 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 cloud 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. - name: Directory readiness description: >- Grade a saved server against a publisher's listing requirements: Anthropic's connector directory or OpenAI's plugin directory. Reported as lane status and coverage, never as a numeric score, and excluded from `pooledConformanceScore`. Deterministic grading is free; model-backed experience observations are an explicit opt-in that consumes MCPJam credits and can never decide a verdict. - name: Registry description: >- Search the scraped MCP directories (Claude, ChatGPT, and any future source), list curated/org registry cards, and install them into a project. Install writes a `servers` row and provenance — it does not open a live session. There is no catalog-uninstall route: delete the project server instead. Directory reads require a bearer (including minted guest tokens) but do not materialize a user. Card/connection reads and all writes are authed-non-guest. paths: /chat-sessions/{sessionId}: get: tags: - Chat sessions summary: Read a chat session's messages description: >- Session metadata plus a bounded window of its raw messages. `index` on each message is its ABSOLUTE position in the stored transcript, not its position in the returned page: trace spans reference messages positionally, so this read and `/trace` join on that number. A transcript that could not be read reports `transcriptUnavailable: true` and a **null** `messageCount` — never 0, which would claim the conversation is empty. operationId: getChatSession parameters: - name: sessionId in: path required: true description: >- The chat session's id — the same id `POST /chat-sessions/messages` returns and `GET /chat-sessions` lists. schema: type: string - name: projectId in: query required: false description: >- Optional project scope. When set, a session in another project answers 404 — the same answer as absence, so this is never an existence oracle. schema: type: string - name: afterMessageIndex in: query required: false description: Start the window at this absolute transcript index. schema: type: integer minimum: 0 - name: limit in: query required: false description: Messages to return, 1–200. Defaults to 50. schema: type: integer minimum: 1 maximum: 200 default: 50 responses: '200': description: The session and one window of its messages. content: application/json: schema: $ref: '#/components/schemas/ChatSessionDetail' '400': $ref: '#/components/responses/ValidationError' '401': $ref: '#/components/responses/Unauthorized' '403': $ref: '#/components/responses/Forbidden' '404': $ref: '#/components/responses/NotFound' '429': $ref: '#/components/responses/RateLimited' '500': $ref: '#/components/responses/InternalError' '502': $ref: '#/components/responses/ServerUnreachable' components: schemas: ChatSessionDetail: type: object required: - sessionId - projectId - origin - modelId - version - startedAt - lastActivityAt - toolMode - environmentId - messageCount - messages properties: sessionId: type: string projectId: type: - string - 'null' origin: type: - string - 'null' modelId: type: - string - 'null' version: type: - integer - 'null' startedAt: type: - integer - 'null' lastActivityAt: type: - integer - 'null' toolMode: type: - string - 'null' enum: - read_only - auto - null environmentId: type: - string - 'null' messageCount: type: - integer - 'null' description: >- NULL — never 0 — when the transcript could not be read. Zero would claim the conversation is empty. transcriptUnavailable: type: boolean messages: type: array items: $ref: '#/components/schemas/ChatMessage' nextMessageIndex: type: integer ChatMessage: type: object required: - index - role - content properties: index: type: integer description: >- ABSOLUTE position in the stored transcript — the number trace spans reference. Never renumbered per page. role: type: string content: description: Scrubbed and bounded message content. truncated: type: boolean 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 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 ServerUnreachable: description: Could not connect to the target MCP server. content: application/json: schema: $ref: '#/components/schemas/Error' example: code: SERVER_UNREACHABLE message: Failed to connect to server 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. ````