# foundation-fsrs-review

`station__foundation__foundation-fsrs-review` · external (needs EXECUTION_BACKEND_URL configured) · domain `foundation` · pv-relevance `non-pv`

FSRS spaced repetition review

> **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

- `difficulty` *number* (required) — Current difficulty value (0.0-1.0)
- `elapsed_days` *integer* (required) — Days since last review
- `rating` *integer* (required) — Rating: 1=Again, 2=Hard, 3=Good, 4=Easy
- `stability` *number* (required) — Current stability value

## Example call

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

{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "station__foundation__foundation-fsrs-review",
    "arguments": {
      "difficulty": 0,
      "elapsed_days": 0,
      "rating": 0,
      "stability": 0
    }
  }
}
```

## Related

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