---
title: "Get an iteration trace"
method: GET
path: "/projects/{projectId}/eval-runs/{runId}/iterations/{iterationId}/trace"
tags: ["Eval runs"]
---

# Get an iteration trace

`GET /projects/{projectId}/eval-runs/{runId}/iterations/{iterationId}/trace`

Full trace envelope for one iteration: conversation messages, expected-vs-actual tool call analysis, and spans. The shape is rich and may evolve — treat it as an open document. Returns `404` with `details.reason: "TRACE_NOT_AVAILABLE"` when the iteration finished without a stored trace.

## Path parameters

- `projectId` string, required
- `runId` string, required
- `iterationId` string, required

## Response `200`

The trace envelope.

- object — Trace document: `messages`, `prompts` (per-prompt expected/actual tool-call analysis), `spans`, and more.

## Other responses

- `401` — 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.
- `403` — Key is valid but not allowed to do this.
- `404` — Unknown project, server, or resource.
- `429` — Per-key rate limit exceeded (60 requests/minute sustained, bursts up to 10). Honor `Retry-After` and back off with jitter.
- `500` — Something failed on MCPJam's side.

---

[API](https://skmtc.net/mcpjam/apis/mcpjam-api.md) · [All operations](https://skmtc.net/mcpjam/apis/mcpjam-api/llms.txt) · [OpenAPI document](https://skmtc-service-staging.skmtc.workers.dev/v1/apis/mcpjam/mcpjam-api/revisions/b8c36aef7731/schema)