stitchkit v0.120.0

⚠️ Breaking changes

Who must act: code importing the MCP server, mountAgent or createToolkit from stitchkit/tools. Code that imports only the registry, tool names, runtime and native tools, the invoker, the OAuth provider or the durability engine from stitchkit/tools changes nothing. See the migration.

• stitchkit/tools — the tools barrel loads no optional peer; MCP, the agent mount and the toolkit have their own subpaths.
  An application serving its operations over HTTP and CLI could not import listToolNames without
  installing @modelcontextprotocol/server and ai: the barrel re-exported the MCP server factories,
  mountAgent and createToolkit, and ESM resolution of the entry needed both optional peers. Import
  the MCP server — createMcpHandler, createMcpHttpRoute, buildMcpServer, mountMcp,
  mountMcpResource, validateMcpSchemas, createStdioMcpServer, bindStdioProcessSignals, the
  catalog stamp and MCP Apps helpers and their config types — from stitchkit/tools/mcp, which already
  exported them; mountAgent, AgentMountConfig and AgentContext from the new
  stitchkit/tools/agent (the ai peer); createToolkit and Toolkit from the new
  stitchkit/tools/toolkit (both peers). A build check walks the built stitchkit/tools graph and fails
  on any optional peer import. // before: import { createMcpHandler, mountAgent } from 'stitchkit/tools'
  → // after: import { createMcpHandler } from 'stitchkit/tools/mcp'; import { mountAgent } from 'stitchkit/tools/agent'.
  ADR 0284;
  migration.
  Affects: stitchkit/tools createMcpHandler, createMcpHttpRoute, buildMcpServer, mountMcp, mountMcpResource, validateMcpSchemas, createStdioMcpServer, bindStdioProcessSignals, inlineMcpAppBundle, mcpCatalogMeta, readMcpCatalogStamp, EXT_APPS_BUNDLE_PLACEHOLDER, MCP_CATALOG_META_KEY, RESOURCE_MIME_TYPE, McpServer, McpHandlerConfig, McpHttpConfig, McpHttpHandler, McpHttpSecurityConfig, McpLegacyPolicy, McpMountConfig, McpServerBuildConfig, McpServerSharedConfig, DirectMcpSurfaceConfig, FiniteMcpSurfaceConfig, McpSurfaceDefinition, McpSurfaceRegistry, McpSchemaValidationConfig, ValidateMcpSchemasConfig, IncompatibleSchemaPolicy, McpStdioHandle, StdioMcpServerConfig, StdioAuthConfig, StdioCloseTarget, StdioProcessSignalsOptions, StdioProcessSignalsBinding, StdioProcessSignalsErrorPhase, McpCatalogStamp, McpResourceDef, McpAppResourceMeta, McpAppCsp, mountAgent, AgentMountConfig, AgentContext, createToolkit, Toolkit

Added

• stitchkit/tools/agent — mountAgent with only Zod and the ai peer; stitchkit/tools/toolkit — createToolkit, the one subpath that needs both the MCP server SDK and ai. Both start evolving.