chore: add AI contribution policy

[dustinbyrne]

Problem

PostHog's main repo has an AI contributions policy and PR-template agent context section. The SDK and agent-extension repos should set the same expectations so AI-assisted contributions are easier to review consistently.

Changes

• Add AI_POLICY.md at the repository root.
• Add an Agent context section to the PR template.
• Adapt the proof-of-work guidance for SDK and agent-extension projects by using repo-neutral testing guidance and calling out example-project smoke tests where applicable.

How did you test this code?

• Verified the markdown changes locally.
• Ran git diff --check.
• Verified the PR template contains exactly one ## 🤖 Agent context section.

Checklist

• Accounted for backwards compatibility of any changes (no breaking changes!)
• Documentation-only change

🤖 Agent context

Autonomy: Human-driven (agent-assisted)

Pi was used to apply the same policy/template update across the SDK and agent-extension repositories. The change was prepared in isolated git worktrees to avoid disturbing existing local branches, then reviewed for duplicate Agent context sections and markdown whitespace issues.

[greptile-apps]

_{Reviews (1): Last reviewed commit: "chore: add AI contribution policy" | Re-trigger Greptile}

[github-actions]

posthog-python Compliance Report

Date: 2026-06-15 21:06:38 UTC
Duration: 176137ms

✅ All Tests Passed!

45/45 tests passed

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Capture Tests

✅ 29/29 tests passed

View Details

Test	Status	Duration
Format Validation.Event Has Required Fields	✅	518ms
Format Validation.Event Has Uuid	✅	1507ms
Format Validation.Event Has Lib Properties	✅	1507ms
Format Validation.Distinct Id Is String	✅	1508ms
Format Validation.Token Is Present	✅	1507ms
Format Validation.Custom Properties Preserved	✅	1507ms
Format Validation.Event Has Timestamp	✅	1507ms
Retry Behavior.Retries On 503	✅	9515ms
Retry Behavior.Does Not Retry On 400	✅	3509ms
Retry Behavior.Does Not Retry On 401	✅	3509ms
Retry Behavior.Respects Retry After Header	✅	9511ms
Retry Behavior.Implements Backoff	✅	23531ms
Retry Behavior.Retries On 500	✅	7509ms
Retry Behavior.Retries On 502	✅	7507ms
Retry Behavior.Retries On 504	✅	7517ms
Retry Behavior.Max Retries Respected	✅	23528ms
Deduplication.Generates Unique Uuids	✅	1500ms
Deduplication.Preserves Uuid On Retry	✅	7512ms
Deduplication.Preserves Uuid And Timestamp On Retry	✅	14525ms
Deduplication.Preserves Uuid And Timestamp On Batch Retry	✅	7509ms
Deduplication.No Duplicate Events In Batch	✅	1504ms
Deduplication.Different Events Have Different Uuids	✅	1509ms
Compression.Sends Gzip When Enabled	✅	1507ms
Batch Format.Uses Proper Batch Structure	✅	1507ms
Batch Format.Flush With No Events Sends Nothing	✅	1005ms
Batch Format.Multiple Events Batched Together	✅	1506ms
Error Handling.Does Not Retry On 403	✅	3508ms
Error Handling.Does Not Retry On 413	✅	3510ms
Error Handling.Retries On 408	✅	7513ms

Feature_Flags Tests

✅ 16/16 tests passed

View Details

Test	Status	Duration
Request Payload.Request With Person Properties Device Id	✅	1004ms
Request Payload.Flags Request Uses V2 Query Param	✅	1007ms
Request Payload.Flags Request Hits Flags Path Not Decide	✅	1007ms
Request Payload.Flags Request Omits Authorization Header	✅	1007ms
Request Payload.Token In Flags Body Matches Init	✅	1007ms
Request Payload.Groups Round Trip	✅	1008ms
Request Payload.Groups Default To Empty Object	✅	1007ms
Request Payload.Person Properties Distinct Id Auto Populated When Caller Omits It	✅	1007ms
Request Payload.Disable Geoip False Propagates As Geoip Disable False	✅	1007ms
Request Payload.Disable Geoip Omitted Defaults To False	✅	1007ms
Request Payload.Flag Keys To Evaluate Contains Only Requested Key	✅	1007ms
Request Lifecycle.No Flags Request On Init Alone	✅	503ms
Request Lifecycle.No Flags Request On Normal Capture	✅	1507ms
Request Lifecycle.Two Flag Calls Produce Two Remote Requests	✅	1012ms
Request Lifecycle.Mock Response Value Is Returned To Caller	✅	1002ms
Side Effect Events.Get Feature Flag Captures Feature Flag Called Event	✅	1510ms