docs: add Pydantic AI integration example

Complete the examples directory with pydantic_ai_example.py showing
governance_dependency usage within Pydantic AI tool functions.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: VladUZH

examples/pydantic_ai_example.py

@@ -0,0 +1,115 @@
+"""Pydantic AI integration example.
+
+Demonstrates using SidClaw governance within Pydantic AI tool functions
+via the governance_dependency helper.
+
+Usage:
+    pip install sidclaw[pydantic-ai] pydantic-ai
+    export SIDCLAW_API_KEY=ai_...
+    export SIDCLAW_AGENT_ID=your-agent-id
+    export OPENAI_API_KEY=sk-...
+    python pydantic_ai_example.py
+"""
+
+import os
+
+from pydantic_ai import Agent, RunContext
+
+from sidclaw import ActionDeniedError, AsyncSidClaw
+from sidclaw.middleware.pydantic_ai import governance_dependency
+
+
+# --- SidClaw client ---
+
+client = AsyncSidClaw(
+    api_key=os.environ["SIDCLAW_API_KEY"],
+    agent_id=os.environ["SIDCLAW_AGENT_ID"],
+)
+
+
+# --- Dependencies ---
+
+class Deps:
+    sidclaw_client: AsyncSidClaw = client
+
+
+# --- Agent ---
+
+agent = Agent("openai:gpt-4", deps_type=Deps)
+
+
+@agent.tool
+async def lookup_customer(ctx: RunContext[Deps], email: str) -> str:
+    """Look up a customer by email address."""
+    gov = governance_dependency(ctx.deps.sidclaw_client)
+    decision = await gov.check(
+        "lookup_customer",
+        target_integration="crm",
+        data_classification="confidential",
+    )
+
+    try:
+        # Your CRM lookup logic here
+        result = f"Customer found: {email} (Enterprise plan)"
+        await gov.record_success(decision.trace_id)
+        return result
+    except Exception as e:
+        await gov.record_error(decision.trace_id, e)
+        raise
+
+
+@agent.tool
+async def send_email(ctx: RunContext[Deps], to: str, subject: str, body: str) -> str:
+    """Send an email to a customer."""
+    gov = governance_dependency(ctx.deps.sidclaw_client)
+
+    try:
+        decision = await gov.check(
+            "send_email",
+            target_integration="email_service",
+            data_classification="confidential",
+        )
+    except ActionDeniedError as e:
+        return f"Email blocked by policy: {e.reason}"
+
+    try:
+        # Your email sending logic here
+        result = f"Email sent to {to}: {subject}"
+        await gov.record_success(decision.trace_id)
+        return result
+    except Exception as e:
+        await gov.record_error(decision.trace_id, e)
+        raise
+
+
+@agent.tool
+async def export_data(ctx: RunContext[Deps], query: str) -> str:
+    """Export customer data (blocked by policy)."""
+    gov = governance_dependency(ctx.deps.sidclaw_client)
+
+    try:
+        decision = await gov.check(
+            "export_data",
+            target_integration="crm",
+            data_classification="restricted",
+        )
+    except ActionDeniedError as e:
+        return f"Data export blocked: {e.reason}"
+
+    # This won't be reached if policy denies
+    return "Export complete"
+
+
+# --- Run ---
+
+async def main():
+    result = await agent.run(
+        "Look up the customer john@example.com and send them a follow-up email",
+        deps=Deps(),
+    )
+    print(result.data)
+
+
+if __name__ == "__main__":
+    import asyncio
+    asyncio.run(main())