> ## Documentation Index
> Fetch the complete documentation index at: https://docs.narrative.io/llms.txt
> Use this file to discover all available pages before exploring further.

# Reserved Tool Name

> A caller-declared tool name collides with a harness tool the platform provides.

**HTTP status:** 400

## Error message

```
caller-declared tool names collide with the tools the harness provides ({reserved_names}): {conflicting_names}
```

Example: `caller-declared tool names collide with the tools the harness provides (bash, file_read, file_write, job_monitor, sleep, wait_for): sleep`.

## When this error occurs

`POST /agents/conversations` or `POST /agents/conversations/{id}/runs` with `config_override` was called with a `tools[].name` that matches one of the platform-provided [harness tools](../agent-conversations#harness-tools). Those names are reserved so the model always sees the platform's implementation for that name — a sandbox tool, or one of the waiting primitives (`sleep`, `job_monitor`, `wait_for`).

## How to fix

Rename the caller-declared tool to something outside the reserved set. Any dash-free name that is not one of the harness tools is accepted; the harness set is small and stable.