Interface McpFormatter

src/mcp.rs:159–204

Trait for formatting MCP configuration for different agents

/// Trait for formatting MCP configuration for different agents
pub trait McpFormatter: Send + Sync {
    /// Format MCP servers into an agent-specific logical `Value` representation.
    ///
    /// This is used as a common in-memory shape across formatters and tests.
    /// On-disk serialization should use `format_to_string()`.
    fn format(&self, servers: &BTreeMap<&str, &McpServerConfig>) -> Value;

    /// Format MCP servers into the agent-specific file content.
    /// By default this returns pretty JSON for agents that use JSON configs.
    fn format_to_string(&self, servers: &BTreeMap<&str, &McpServerConfig>) -> Result<String> {
        let output = self.format(servers);
        serde_json::to_string_pretty(&output).context("Failed to serialize MCP config")
    }

    /// Parse existing configuration file to extract mcpServers
    fn parse_existing(&self, content: &str) -> Result<BTreeMap<String, Value>>;

    /// Merge new servers with existing configuration
    fn merge(
        &self,
        existing_content: &str,
        new_servers: &BTreeMap<&str, &McpServerConfig>,
    ) -> Result<String>;

    /// Remove servers that are no longer in the configuration
    /// Default implementation just calls merge, but specific formatters can override
    fn cleanup_removed_servers(
        &self,
        existing_content: &str,
        new_servers: &BTreeMap<&str, &McpServerConfig>,
    ) -> Result<String> {
        self.merge(existing_content, new_servers)
    }

    /// Whether this formatter wraps mcpServers in another key
    fn wrapper_key(&self) -> Option<&'static str> {
        None
    }

    /// Whether the formatter should preserve unrelated top-level settings when
    /// running in Overwrite mode. Some agents (Gemini, OpenCode) keep other
    /// settings in their config files and we shouldn't clobber them.
    fn preserve_on_overwrite(&self) -> bool {
        false
    }
}

// =============================================================================
// Standard MCP Helper Functions