Documentation
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Index ¶
Constants ¶
This section is empty.
Variables ¶
var ( // ErrNotConnected is returned when a tool call is attempted on a disconnected server. ErrNotConnected = errors.New("mcp server not connected") // ErrAlreadyConnected is returned when Connect is called on an already-connected server. ErrAlreadyConnected = errors.New("mcp server already connected") // ErrInvalidConfig is returned when the server configuration is invalid. ErrInvalidConfig = errors.New("invalid mcp configuration") )
Functions ¶
This section is empty.
Types ¶
type HTTPTransportConfig ¶
type HTTPTransportConfig struct {
// URL is the MCP server endpoint.
// When URLFunc is also set, URL is used only for initial tool discovery
// at startup; all subsequent tool calls route through URLFunc.
URL string
// URLFunc dynamically resolves the MCP server URL per tool execution.
// It receives the tool execution context which carries run variables
// (tenant_id, user_id, etc.) accessible via tool.GetVariable().
// When set, the MCPServer pools and reuses sessions per resolved URL.
// If nil, all tool calls use the static URL.
URLFunc func(ctx context.Context) (string, error)
// HTTPClient allows full control over the HTTP client used for requests.
// Users can configure TLS, timeouts, and inject auth via custom
// RoundTripper middleware.
// If nil, a default client is used.
HTTPClient *http.Client
// Headers are additional HTTP headers sent with every request.
// Use for static auth tokens: {"Authorization": "Bearer xxx"}.
Headers map[string]string
// HeaderFunc is called before each request to produce dynamic headers.
// This takes precedence over static Headers for the same key.
// Useful for OAuth tokens that rotate.
HeaderFunc func() (map[string]string, error)
}
HTTPTransportConfig configures a Streamable HTTP MCP server connection.
type MCPServer ¶
type MCPServer struct {
// contains filtered or unexported fields
}
MCPServer represents a connection to a single MCP server. It manages the connection lifecycle and exposes discovered tools as tool.Tool implementations.
func NewMCPServer ¶
func NewMCPServer(config *MCPServerConfig) (*MCPServer, error)
NewMCPServer creates a new MCP server connection manager. Does not connect yet — call Connect() to establish the connection, or use RegisterServer() for convenience.
func RegisterServer ¶
func RegisterServer(ctx context.Context, registrar ToolRegistrar, config *MCPServerConfig) (*MCPServer, error)
RegisterServer connects to an MCP server, discovers tools, and registers them with the given registrar (typically *agentpg.Client). Returns the MCPServer for lifecycle management. The caller must call Close() when the server is no longer needed (typically via defer).
Must be called before client.Start().
func RegisterServerLazy ¶ added in v0.3.3
func RegisterServerLazy(registrar ToolRegistrar, config *MCPServerConfig) (*MCPServer, error)
RegisterServerLazy creates an MCPServer without connecting. Tools are discovered and registered lazily on the first tool call (or via an explicit EnsureConnected call). This is useful for multi-tenant setups where the MCP URL is only known at request time via URLFunc.
func (*MCPServer) EnsureConnected ¶ added in v0.3.3
EnsureConnected connects to the MCP server if not already connected. Idempotent and thread-safe — safe to call from multiple goroutines. When URLFunc is set and URL is empty, the first call resolves the discovery URL from URLFunc(ctx).
type MCPServerConfig ¶
type MCPServerConfig struct {
// Name is the unique identifier for this MCP server.
// Used as namespace prefix for tools: "{Name}__{tool_name}".
// Must be non-empty.
Name string
// Transport: exactly one of Stdio or HTTP must be set.
Stdio *StdioTransportConfig
HTTP *HTTPTransportConfig
// DisableToolPrefix disables tool name prefixing.
// When false (default), tools are registered as "{Name}__{tool_name}".
// When true, tools use their original MCP names (risk of collision).
DisableToolPrefix bool
// ToolFilter optionally filters which tools to expose from this server.
// Receives the original MCP tool name (without prefix).
// Return true to include the tool, false to exclude it.
// If nil, all tools are exposed.
ToolFilter func(toolName string) bool
// Reconnect configures automatic reconnection behavior.
// If nil, no automatic reconnection is performed.
Reconnect *ReconnectConfig
}
MCPServerConfig configures a connection to an MCP server.
type MCPTool ¶
type MCPTool struct {
// contains filtered or unexported fields
}
MCPTool bridges an MCP server tool to the agentpg tool.Tool interface. It is created by MCPServer during tool discovery.
func (*MCPTool) Description ¶
Description returns the tool description from the MCP server.
func (*MCPTool) InputSchema ¶
func (t *MCPTool) InputSchema() tool.ToolSchema
InputSchema returns the tool's input schema converted to agentpg format.
type ReconnectConfig ¶
type ReconnectConfig struct {
// MaxRetries is the maximum number of reconnection attempts.
// 0 means unlimited retries.
// Default: 0 (unlimited)
MaxRetries int
// InitialDelay is the delay before the first reconnection attempt.
// Default: 1 second
InitialDelay time.Duration
// MaxDelay caps the exponential backoff.
// Default: 30 seconds
MaxDelay time.Duration
}
ReconnectConfig controls automatic reconnection to MCP servers.
type StdioTransportConfig ¶
type StdioTransportConfig struct {
// Command is the path to the MCP server executable.
Command string
// Args are the command-line arguments.
Args []string
// Env are additional environment variables for the subprocess.
// These are appended to os.Environ().
// Use this for passing API keys, tokens, etc.
Env []string
// Dir is the working directory for the subprocess.
// If empty, the current working directory is used.
Dir string
}
StdioTransportConfig configures a stdio (subprocess) MCP server connection.
type ToolRegistrar ¶
ToolRegistrar is the minimal interface for registering tools. Satisfied by *agentpg.Client[TTx].
Source Files