# `ExMCP.Validation.ToolName`
[🔗](https://github.com/azmaveth/ex_mcp/blob/v1.0.0/lib/ex_mcp/validation/tool_name.ex#L1)

Validates MCP tool names according to the 2025-11-25 specification.

Tool names must:
- Be 1-128 characters long
- Only contain alphanumeric characters, dots, hyphens, and underscores
- Match the pattern: `^[a-zA-Z0-9_.\-]+$`

# `valid?`

```elixir
@spec valid?(String.t()) :: boolean()
```

Returns true if the tool name is valid.

# `validate`

```elixir
@spec validate(String.t()) :: {:ok, String.t()} | {:error, String.t()}
```

Validates a tool name.

Returns `{:ok, name}` if valid, `{:error, reason}` if invalid.

## Examples

    iex> ExMCP.Validation.ToolName.validate("my_tool")
    {:ok, "my_tool"}

    iex> ExMCP.Validation.ToolName.validate("my tool")
    {:error, "Tool name contains invalid characters. Must match [a-zA-Z0-9_.\\-]+"}

    iex> ExMCP.Validation.ToolName.validate("")
    {:error, "Tool name must be between 1 and 128 characters"}

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*Consult [api-reference.md](api-reference.md) for complete listing*