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Documentation Index

Fetch the complete documentation index at: https://docs.grantex.dev/llms.txt

Use this file to discover all available pages before exploring further.

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What it does

This example demonstrates the @grantex/anthropic integration by building scope-enforced tools for Claude:
  1. Register an agent and obtain a grant token via the sandbox flow
  2. Create scoped tools using createGrantexTool with JSON Schema (calendar:read, email:send)
  3. Use GrantexToolRegistry to manage tools and dispatch tool_use blocks
  4. Invoke tools via client.messages.create() (if ANTHROPIC_API_KEY is set) or directly
  5. Demonstrate GrantexScopeError — attempting to execute a tool with storage:delete (a scope not in the grant) throws a GrantexScopeError with requiredScope and grantedScopes properties
  6. Inspect scopes offline using getGrantScopes() to decode the JWT without a network call
  7. Inspect the audit trail to see the logged actions

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Prerequisites

  • Node.js 18+
  • Docker (Docker Desktop or Docker Engine with Compose)

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Run

Start the local Grantex stack from the repository root: 
docker compose up --build
In a separate terminal, run the example: 
cd examples/anthropic-tool-use
npm install
npm start
To use Claude for real tool use instead of direct invocation, set ANTHROPIC_API_KEY: 
ANTHROPIC_API_KEY=sk-ant-... npm start

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Expected output

Without ANTHROPIC_API_KEY (direct invocation): 
Agent registered: ag_01HXYZ...
Grant token received, grantId: grnt_01HXYZ...
Tools created: read_calendar, send_email (registry has 2 tools)

--- Invoking tools directly (no ANTHROPIC_API_KEY set) ---
Calendar result: {"date":"today","events":[{"title":"Team standup","time":"9:00 AM"},{"title":"Design review","time":"2:00 PM"}]}
Email result: {"sent":true,"to":"alice@example.com","subject":"Today's events","bodyLength":49}

--- Testing scope enforcement ---
GrantexScopeError caught:
  Required scope:  storage:delete
  Granted scopes:  calendar:read, email:send

--- Inspecting grant scopes ---
Scopes in token: calendar:read, email:send

--- Audit trail ---
  [success] tool:read_calendar — 2026-03-30T12:00:00.000Z
  [success] tool:send_email — 2026-03-30T12:00:01.000Z

Done! Anthropic SDK integration demo complete.

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Environment variables

VariableDefaultDescription
GRANTEX_URLhttp://localhost:3001Base URL of the Grantex auth service
GRANTEX_API_KEYsandbox-api-key-localAPI key. Use a sandbox key for auto-approval
ANTHROPIC_API_KEY(none)Optional. Set to use Claude for real tool use

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Source code

The full source is in examples/anthropic-tool-use/src/index.ts.