# trial-interim-analyze

`station__trial__trial-interim-analyze` · external (needs EXECUTION_BACKEND_URL configured) · domain `trial` · pv-relevance `pv-core`

Run interim analysis using OBF or Pocock boundaries.

> **Note:** This tool routes through an external execution backend. If `EXECUTION_BACKEND_URL` is unset on the server, calls return JSON-RPC error `-32603 "Tool execution backend not configured"`. Tools with `backend: native` execute in-process and are always callable.

## Agent metadata

- `idempotent`: unknown
- `read_only`: unknown
- `expected_latency_ms`: unknown (not yet contract-tested)
- `cost_tokens_estimate`: unknown

## Input schema

- `control_n` *integer* (required) — Total subjects in control arm
- `control_successes` *integer* (required) — Successes observed in control arm
- `information_fraction` *number* (required) — Information fraction accumulated (0 < t ≤ 1)
- `method` *string* (required)
- `protocol_json` *string* (required) — Protocol as JSON (for alpha, safety boundary, and adaptation rules)
- `safety_events` *integer* (required)
- `treatment_n` *integer* (required) — Total subjects in treatment arm
- `treatment_successes` *integer* (required) — Successes observed in treatment arm

## Example call

```json
POST /api/mcp
Content-Type: application/json

{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "station__trial__trial-interim-analyze",
    "arguments": {
      "control_n": 0,
      "control_successes": 0,
      "information_fraction": 0,
      "method": "",
      "protocol_json": "",
      "safety_events": 0,
      "treatment_n": 0,
      "treatment_successes": 0
    }
  }
}
```

## Related

- [/tools](/tools) — all 3062 tools
- [/tools/trial__trial-interim-analyze](/tools/trial__trial-interim-analyze) — HTML page
- [/tools/trial__trial-interim-analyze/json](/tools/trial__trial-interim-analyze/json) — JSON form (agent-friendly)
- [/api/mcp](/api/mcp) — endpoint
- [/AGENTS.md](/AGENTS.md) — agent guide