> ## 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.

# Invalid Tool Alias

> One or more tool aliases do not match the required regex.

**HTTP status:** 400

## Error message

```
invalid tool aliases (must match ^[a-zA-Z][a-zA-Z0-9]{0,7}$): {bad-aliases}
```

## When this error occurs

Every entry under `defaults.mcp_servers[].alias` must match `^[a-zA-Z][a-zA-Z0-9]{0,7}$`:

* 1–8 characters total,
* starts with an ASCII letter,
* contains only ASCII letters and digits — **no underscores, dashes, or other punctuation**.

The dash is reserved as the separator in the wire form `{alias}-{tool_name}` that the model sees,
so aliases can't contain dashes themselves.

Caller-declared tools (under top-level `tools[]`) have no alias — their `name` is what the model
sees on the wire. See
[Invalid Caller-Declared Tool Name](./invalid-caller-tool-name) for the analogous rules on those
names.

## How to fix

| Bad                            | Fix                  |
| ------------------------------ | -------------------- |
| `my_docs` (underscore)         | `mydocs`             |
| `docs-v2` (dash)               | `docsv2`             |
| `1docs` (digit-leading)        | `docs1`              |
| `verylongdocsalias` (>8 chars) | `docs` or `verylong` |

Re-post the request with the corrected aliases.