Struct McpConfig 

pub struct McpConfig {
    pub name: String,
    pub version: String,
    pub description: Option<String>,
    pub tools_enabled: bool,
    pub allowed_tags: HashSet<String>,
    pub allowed_path_prefixes: Vec<String>,
    pub admin_token: Option<String>,
    pub expose_detailed_errors: bool,
    pub max_tools: usize,
    pub invocation_mode: InvocationMode,
    pub tool_policy: ToolPolicy,
}

Configuration for the native MCP server.

This is the primary way users control what gets exposed as tools, authentication for MCP clients, transport behavior, etc.

Fields

name: String

Human-friendly name of this MCP server (shown to agents).

version: String

Version string.

description: Option<String>

Optional description.

tools_enabled: bool

Whether tool discovery and calling is enabled.

allowed_tags: HashSet<String>

Explicitly allowed tags. Only routes that have at least one of these tags (via OpenAPI tags or future route metadata) will be exposed as tools.

Empty set + no other allow rules = nothing is exposed (safe default).

allowed_path_prefixes: Vec<String>

Explicit path prefixes that are allowed to become tools. Example: ["/api/public", "/agent"]

admin_token: Option<String>

Admin / MCP client token.

When set, MCP clients must present this (via header or query param, transport dependent) to use discovery or invocation.

expose_detailed_errors: bool

Whether to include detailed error information in tool responses. In production you usually want this false (similar to RUSTAPI_ENV=production).

max_tools: usize

Maximum number of tools to advertise in one tools/list response. Helps protect against very large route sets.

invocation_mode: InvocationMode

How tools/call should be executed. Proxy (default) always goes over HTTP (correct and works for external targets). InProcess / Auto are for when an in-process RustApi instance is available.

tool_policy: ToolPolicy

Permission policy for which operations are exposed as MCP tools.

Framework-native guardrail. By default we are conservative for agent use: ReadOnly (only safe methods like GET are exposed unless you opt into writes).

This addresses the blast radius concern when agents can call destructive endpoints.

Implementations

impl McpConfig

pub fn new() -> Self

Create a new config with reasonable defaults.

pub fn name(self, name: impl Into<String>) -> Self

Set the name advertised to MCP clients.

pub fn version(self, version: impl Into<String>) -> Self

Set the version advertised to MCP clients.

pub fn description(self, desc: impl Into<String>) -> Self

Set a human description.

pub fn enable_tools(self, enabled: bool) -> Self

Enable or disable the tools capability entirely.

pub fn allowed_tags<I, S>(self, tags: I) -> Self

where I: IntoIterator<Item = S>, S: Into<String>,

Allow tools only for routes that carry at least one of the given tags.

This is the recommended way to safely expose a curated surface to agents.

pub fn allow_path_prefix(self, prefix: impl Into<String>) -> Self

Add a path prefix that is allowed to be exposed as tools.

pub fn admin_token(self, token: impl Into<String>) -> Self

Require this token for MCP clients (discovery + calls).

pub fn expose_detailed_errors(self, expose: bool) -> Self

Control whether tool responses include full internal error details.

pub fn max_tools(self, max: usize) -> Self

Set the maximum number of tools to list.

pub fn invocation_mode(self, mode: InvocationMode) -> Self

Choose invocation strategy for tool calls.

pub fn tool_policy(self, policy: ToolPolicy) -> Self

Set the permission policy for exposing tools.

ReadOnly is the safe default when agents will call your tools. Only GET/HEAD/OPTIONS operations are turned into tools.

Use All if you explicitly want agents to perform writes (and you have strong allowed_tags + confirmation flows).

Trait Implementations

impl Clone for McpConfig

fn clone(&self) -> McpConfig

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for McpConfig

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for McpConfig

fn default() -> Self

Returns the “default value” for a type.