task_plan.md

Task Plan: Implement Kiro AWS EventStream Protocol Handler

Goal

Implement the AWS EventStream protocol handler so Kiro provider in codev can actually perform inference (like 9router's MITM handler does).

Background

• 9router uses MITM proxy: intercepts Kiro IDE's EventStream requests → converts to OpenAI → routes inference → converts back to EventStream
• codev needs a native protocol handler that speaks EventStream directly to q.us-east-1.amazonaws.com / runtime.us-east-1.kiro.dev
• Current Kiro provider uses anthropic-messages as placeholder — inference fails

Phases

Phase 1: AWS EventStream Binary Framing

• Create CRC32 utility (polynomial 0xEDB88320)
• Create EventStream frame builder (prelude + headers + payload + CRC)
• Implement Smithy system headers (:message-type, :event-type, :content-type)
• Implement event types: initial-response, assistantResponseEvent, reasoningContentEvent, toolUseEvent, messageStopEvent, usageEvent

Phase 2: CodeWhisperer ↔ OpenAI Format Conversion

• Convert CodeWhisperer conversationState → OpenAI messages[]
• Handle userInputMessage (text, images, toolResults)
• Handle assistantResponseMessage (text, toolUses)
• Extract tool definitions from request
• Convert OpenAI SSE chunks → EventStream frames (streaming)

Phase 3: Protocol Handler Integration

• Create aws-eventstream protocol in src/services/llm/protocols/
• Register in src/services/llm/protocols/index.ts
• Update Kiro provider to use aws-eventstream protocol
• Implement auth header resolution (Bearer access_token + profile_arn + region)

Phase 4: Testing & Integration

• Test with imported refresh token
• Verify model listing works
• Test inference end-to-end
• Handle token refresh on 401

Reference

• 9router: src/mitm/handlers/kiro.js (580 lines) — complete conversion pipeline
• Key endpoints: https://codewhisperer.{region}.amazonaws.com (models), https://q.{region}.amazonaws.com (inference)
• EventStream spec: AWS Smithy protocol, binary framing with CRC32