# List traces URL: https://docs.hanzo.ai/docs/openapi/eval/get-eval-traces > The traces behind your evaluations — one per model call an evaluation made, carrying its input, output, model and timing — narrowed by any of sessionId, runName and datasetName. `GET /v1/eval/traces` > [Eval →](https://docs.hanzo.ai/docs/openapi/eval) · [All API references →](https://docs.hanzo.ai/docs/openapi) · [Get started →](https://docs.hanzo.ai/docs/guides) | | | | ------------- | -------------------------------------- | | **Address** | `https://api.hanzo.ai/v1/eval/traces` | | **Method** | `GET` | | **Operation** | `get_eval_traces` | | **Auth** | `Authorization: Bearer $HANZO_API_KEY` | The traces behind your evaluations — one per model call an evaluation made, carrying its input, output, model and timing — narrowed by any of sessionId, runName and datasetName. Scoped by org AND by project: the project is the caller's server-minted scope, not a parameter, so it cannot be widened by asking. Requires a validated principal; 401 without one. Traces live in the datastore, so a deployment with none wired answers 503 rather than an empty page. ## Request 4 fields. | Field | In | Type | Required | Description | | ------------- | ----- | ------- | -------- | --------------------------------------------------------------------- | | `sessionId` | query | string | — | SessionID narrows to one session, which for an evaluation is one run. | | `runName` | query | string | — | RunName narrows to the calls one run made. | | `datasetName` | query | string | — | Dataset narrows to the calls made against one dataset. | | `limit` | query | integer | — | | ## Response | Status | Body | Meaning | | --------- | --------------- | ------- | | `200` | eval.traceList | ok | | `default` | problem-details | refused | `200` body — 16 fields. | Field | In | Type | Always | Description | | ---------------------- | ---- | ----------------- | ------ | ----------------------------------------------------------------------------------------------------------------------------------------------------------- | | `data` | body | eval.traceView\[] | — | Data is the caller org's traces matching the filters, bounded by limit. | | `data[].apiKeyHash` | body | string | — | APIKeyHash is the non-reversible credential ref (never a plaintext key), so a trace correlates to the key that drove it without the store holding a secret. | | `data[].datasetItemId` | body | string | — | ItemID is the example the call answered. | | `data[].datasetName` | body | string | — | Dataset is the set the graded example came from. | | `data[].endTime` | body | string | — | EndTime is when it returned. | | `data[].id` | body | string | — | ID is the trace's handle, the value a score points at. | | `data[].input` | body | any | — | Input is what the model was given. | | `data[].latencyMs` | body | number (double) | — | LatencyMs is EndTime-StartTime in milliseconds, nil when the trace carries no timing (so the console renders "—", never a fabricated 0). | | `data[].model` | body | string | — | Model is the model that answered. | | `data[].name` | body | string | — | Name is the trace's label, "eval:\" for a call a run made. | | `data[].output` | body | string | — | Output is what it answered. | | `data[].projectId` | body | string | — | ProjectID is the sub-scope within the org the call was made under. | | `data[].runName` | body | string | — | RunName is the run the call belongs to. | | `data[].sessionId` | body | string | — | SessionID groups the calls of one run. | | `data[].startTime` | body | string | — | StartTime is when the call began. | | `data[].timestamp` | body | string | — | Timestamp is the trace's own clock, equal to StartTime for a timed call. | Failure carries the platform error shape — see [Errors](https://docs.hanzo.ai/docs/errors). ## Examples **CLI** ```bash hanzo eval traces ``` **SDK** **.ts** ```ts import { Configuration, EvalApi } from 'hanzoai'; const api = new EvalApi(new Configuration({ accessToken: process.env.HANZO_API_KEY })); const { data } = await api.getEvalTraces(); ``` **.py** ```python from hanzoai.cloud import ApiClient, Configuration from hanzoai.cloud.api import EvalApi client = ApiClient(Configuration(access_token=os.environ["HANZO_API_KEY"])) result = EvalApi(client).get_eval_traces() ``` **.go** ```go cfg := hanzoai.NewConfiguration() cfg.AddDefaultHeader("Authorization", "Bearer "+os.Getenv("HANZO_API_KEY")) client := hanzoai.NewAPIClient(cfg) resp, _, err := client.EvalAPI.GetEvalTraces(context.Background()).Execute() if err != nil { return err } ``` **.rs** ```rust use hanzo_client::apis::{configuration::Configuration, eval_api}; let mut cfg = Configuration::new(); cfg.bearer_access_token = std::env::var("HANZO_API_KEY").ok(); let result = eval_api::get_eval_traces(&cfg, Default::default()).await?; ``` **.java** ```java import ai.hanzo.cloud.ApiClient; import ai.hanzo.cloud.api.EvalApi; ApiClient client = new ApiClient(); client.setBearerToken(System.getenv("HANZO_API_KEY")); var result = new EvalApi(client).getEvalTraces(); ``` **HTTP** ```bash curl https://api.hanzo.ai/v1/eval/traces \ -H "Authorization: Bearer $HANZO_API_KEY" ``` **MCP** MCP reaches **eval** through the `eval` tool, which names its 16 operations with its own verbs — this one among them, under a name only MCP declares. `describe` explains any of them: ```bash curl -X POST https://api.hanzo.ai/v1/mcp \ -H "Content-Type: application/json" \ -d '{ "jsonrpc": "2.0", "id": 1, "method": "tools/call", "params": { "name": "describe", "arguments": { "op": "list_eval_datasets" } } }' ``` --- [Eval API](https://docs.hanzo.ai/docs/openapi/eval) · [All Hanzo APIs](https://docs.hanzo.ai/docs/openapi) · [Interactive reference](https://docs.hanzo.ai/docs/openapi/reference)