Adapt to the latest WebMCP spec#5
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igrigorik merged 1 commit intoigrigorik:mainfrom Jan 28, 2026
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| '@types': path.resolve(__dirname, './src/types'), | ||
| // Use CSP-safe Ajv shim - real Ajv uses new Function() which violates extension CSP | ||
| // Also fixes ESM import issue (ajv doesn't have default export in ESM) | ||
| ajv: path.resolve(__dirname, 'src/lib/ajv-csp-safe.js'), |
beaufortfrancois
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beaufortfrancois
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Nice! I've tried it locally and it works great!
| name: 'my_tool', | ||
| description: 'Does something useful', | ||
| inputSchema: { type: 'object', properties: {} }, | ||
| execute: async (args, agent) => { |
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Nit: async is optional there.
| - `unregisterTool(name)` - Remove a tool by name | ||
| - `clearContext()` - Remove all tools | ||
| - `listTools()` - Get current tool definitions (without execute functions) | ||
| - `callTool(name, args)` - Invoke a tool (used by the agent, not typically by tools) |
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Should it be renamed to executeTool?
| // Create agent context for this tool execution | ||
| const agentContext = createAgentContext(); | ||
| // Per WebMCP spec: execute(params, agent) | ||
| return await Promise.resolve(tool.execute(params, agentContext)); |
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Naive question: Why not return await tool.execute(params, agentContext); only?
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Align WebMCP polyfill with Chrome Canary's native implementation
Tested in 146.0.7652.0 canary
Separated page-side and agent-side APIs to match Chrome's WebMCP spec:
navigator.modelContextfor pages to register tools (registerTool,unregisterTool,provideContext,clearContext) andnavigator.modelContextTestingfor agents to discover/execute tools (listTools,executeTool,registerToolsChangedCallback)Fixed Chrome native API compatibility:
executeTool()now accepts args as JSON string (Chrome's format), andinputSchemareturned fromlistTools()is automatically parsed from JSON string to object inlifecycle.tsAdded CSP-safe Ajv shim (
src/lib/ajv-csp-safe.js) to replace real Ajv which usesnew Function()that violates Chrome extension CSP, also fixing the ESM default export issueUpdated page-bridge.js to use spec-aligned method names (
executeTool,registerToolsChangedCallback) and removed dead fallback code that referenced non-existent methods on the separated APIsMaintained backward compatibility via
window.agentwhich combines both page-side and agent-side methods for existing scripts, while new code should use the separatedmodelContext/modelContextTestingAPIs