[Bug] Anthropic API Error: 500 Internal Server Error during multiple planning iterations followed by error in compaction

Bug Description
Persistent API Error: 500 when doing several planning iterations: API Error: 500 {"type":"error","error":{"type":"api_error","
message":"Internal server
error"},"request_id":"req_011CWwJthqeiwqbHGcAkELDh"}

How to reproduce:
Run several iterations of the plan with long messages and adjustments to the plan. On n'th iteration, Claude throws an error and can't compact.

<img width="1194" height="1450" alt="Image" src="https://github.com/user-attachments/assets/f9139050-38ec-42f2-91cd-f2a296c0ac56" />

Environment Info

• Platform: darwin
• Terminal: WarpTerminal
• Version: 2.1.2
• Feedback ID: f9eafc1e-d663-4fd1-afed-cabe84830e29

Errors

[{"error":"Error: Plugin MCP server error - mcp-config-invalid: MCP server github invalid: Missing environment variables: GITHUB_PERSONAL_ACCESS_TOKEN\n    at $OT (/$bunfs/root/claude:2013:23427)\n    at async <anonymous> (/$bunfs/root/claude:5009:878)\n    at processTicksAndRejections (native:7:39)","timestamp":"2026-01-09T01:12:01.098Z"},{"error":"Error: NON-FATAL: Lock acquisition failed for /Users/kirso/.local/share/claude/versions/2.1.2 (expected in multi-process scenarios)\n    at HQR (/$bunfs/root/claude:2960:2165)\n    at MKA (/$bunfs/root/claude:2960:1885)\n    at processTicksAndRejections (native:7:39)","timestamp":"2026-01-09T01:12:01.457Z"},{"error":"Error: Plugin MCP server error - mcp-config-invalid: MCP server github invalid: Missing environment variables: GITHUB_PERSONAL_ACCESS_TOKEN\n    at $OT (/$bunfs/root/claude:2013:23427)\n    at async W (/$bunfs/root/claude:2964:6838)\n    at processTicksAndRejections (native:7:39)","timestamp":"2026-01-09T01:12:07.332Z"},{"error":"Error: Plugin MCP server error - mcp-config-invalid: MCP server github invalid: Missing environment variables: GITHUB_PERSONAL_ACCESS_TOKEN\n    at $OT (/$bunfs/root/claude:2013:23427)\n    at async J (/$bunfs/root/claude:2964:7354)\n    at processTicksAndRejections (native:7:39)","timestamp":"2026-01-09T01:12:07.332Z"},{"error":"SyntaxError: JSON Parse error: Property name must be a string literal\n    at <parse> (:0)\n    at parse (unknown)\n    at <anonymous> (/$bunfs/root/claude:78:708)\n    at A (/$bunfs/root/claude:11:7245)\n    at Le7 (/$bunfs/root/claude:2992:13602)\n    at async WKB (/$bunfs/root/claude:2992:16388)\n    at processTicksAndRejections (native:7:39)","timestamp":"2026-01-09T01:12:07.351Z"},{"error":"Error: EISDIR: illegal operation on a directory, read\n    at readFileSync (unknown)\n    at <anonymous> (/$bunfs/root/claude:12:528)\n    at z2 (/$bunfs/root/claude:11:34141)\n    at readFileSync (/$bunfs/root/claude:12:487)\n    at Xb_ (/$bunfs/root/claude:4742:23129)\n    at call (/$bunfs/root/claude:1622:945)\n    at call (/$bunfs/root/claude:1618:6420)\n    at X_8 (/$bunfs/root/claude:3296:27264)\n    at processTicksAndRejections (native:7:39)","timestamp":"2026-01-09T01:19:14.230Z"},{"error":"Error: EISDIR: illegal operation on a directory, read\n    at readFileSync (unknown)\n    at <anonymous> (/$bunfs/root/claude:12:528)\n    at z2 (/$bunfs/root/claude:11:34141)\n    at readFileSync (/$bunfs/root/claude:12:487)\n    at Xb_ (/$bunfs/root/claude:4742:23129)\n    at call (/$bunfs/root/claude:1622:945)\n    at call (/$bunfs/root/claude:1618:6420)\n    at X_8 (/$bunfs/root/claude:3296:27264)\n    at processTicksAndRejections (native:7:39)","timestamp":"2026-01-09T01:19:15.067Z"},{"error":"Error: Failed to fetch version from https://storage.googleapis.com/claude-code-dist-86c565f3-f756-42ad-8dfa-d59b1c096819/claude-code-releases/latest: ECONNREFUSED\n    at io7 (/$bunfs/root/claude:2958:28008)\n    at processTicksAndRejections (native:7:39)","timestamp":"2026-01-09T02:24:48.581Z"},{"error":"Error: Failed to fetch version from latest: Error: ECONNREFUSED\n    at io7 (/$bunfs/root/claude:2958:28063)\n    at processTicksAndRejections (native:7:39)","timestamp":"2026-01-09T02:24:48.582Z"},{"error":"Error: 1P event logging: 3 events failed to export\n    at queueFailedEvents (/$bunfs/root/claude:212:2077)\n    at async doExport (/$bunfs/root/claude:212:1257)\n    at processTicksAndRejections (native:7:39)","timestamp":"2026-01-09T02:24:53.585Z"},{"error":"Error: {\"message\":\"Failed to export 3 events\",\"originalLine\":\"212\",\"originalColumn\":\"1336\",\"line\":\"212\",\"column\":\"1336\",\"sourceURL\":\"/$bunfs/root/claude\",\"stack\":\"Error: Failed to export 3 events\\n    at doExport (/$bunfs/root/claude:212:1336)\\n    at processTicksAndRejections (native:7:39)\",\"name\":\"Error\"}\n    at error (/$bunfs/root/claude:1765:25028)\n    at <anonymous> (/$bunfs/root/claude:206:38554)\n    at sJD (/$bunfs/root/claude:206:39098)\n    at <anonymous> (/$bunfs/root/claude:207:17366)\n    at processTicksAndRejections (native:7:39)","timestamp":"2026-01-09T02:24:53.586Z"},{"error":"Error: Failed to fetch version from https://storage.googleapis.com/claude-code-dist-86c565f3-f756-42ad-8dfa-d59b1c096819/claude-code-releases/latest: ECONN

Note: Error logs were truncated.