Struct McpSpecBuilder 

pub struct McpSpecBuilder { /* private fields */ }

Builder for McpSpec.

Implementations

impl McpSpecBuilder

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

Set the consumer’s owner tag (recorded in the sidecar ownership ledger).

pub fn adopt_unowned(self, adopt: bool) -> Self

Adopt a config entry that exists on disk but has no recorded owner.

Use this to recover from a crash between an earlier install’s config write and ledger record. With false (default) such entries are refused with AgentConfigError::NotOwnedByCaller (actual: None) to avoid silently taking over a hand-installed entry.

pub fn stdio<I, S>(self, command: impl Into<String>, args: I) -> Self

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

Configure a stdio launcher.

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

Configure an HTTP transport.

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

Configure an SSE transport.

pub fn env(self, key: impl Into<String>, value: impl Into<String>) -> Self

Set or replace one environment variable on a stdio transport.

Calling this before configuring stdio, or after configuring a non-stdio transport, records a builder error returned by try_build.

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

Set an env variable to a placeholder that references the host environment, e.g. GITHUB_TOKEN=${GITHUB_TOKEN}.

Placeholders are not treated as inline secrets by the local-scope secret policy because the actual secret value is not written.

pub fn env_placeholder( self, key: impl Into<String>, placeholder: impl Into<String>, ) -> Self

Set an env variable to a caller-provided placeholder.

This is useful when a harness supports its own placeholder syntax. The value is still validated as a normal MCP env value.

pub fn header(self, key: impl Into<String>, value: impl Into<String>) -> Self

Set or replace one header on an HTTP/SSE transport.

Calling this before configuring HTTP/SSE, or after configuring stdio, records a builder error returned by try_build.

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

Set a human-friendly display name.

pub fn allow_local_inline_secrets(self) -> Self

Explicitly allow likely secret env values in project-local MCP configs.

The default policy refuses this because local project config files are easy to commit, sync, or share accidentally.

pub fn build(self) -> McpSpec

Finalize the spec, panicking on missing or invalid fields.

Convenience wrapper around try_build() for tests and examples. Production code should prefer try_build() to propagate errors instead of panicking.

Panics

Panics if required fields are missing or validation fails.

pub fn try_build(self) -> Result<McpSpec, AgentConfigError>

Finalize the spec, returning Result on missing or invalid fields.

This is the recommended way to build a spec in production code. See crate-level documentation for a full example.

Errors

• AgentConfigError::Other when an earlier builder method recorded a deferred error (e.g. invalid env var name).
• AgentConfigError::MissingSpecField with field = "owner" or field = "transport" when those calls were skipped.
• AgentConfigError::InvalidTag when name, owner_tag, or any transport field (command path, env var, header value) fails identifier or transport validation.

Trait Implementations

impl Clone for McpSpecBuilder

fn clone(&self) -> McpSpecBuilder

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for McpSpecBuilder

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

Formats the value using the given formatter.