Previous fix only injected billing header + agent identifier (2 blocks).
Anthropic's updated detection now validates system prompt content depth:
- Block count (needs 4-6 blocks, not 2)
- Cache control scopes (org for agent, global for core prompt)
- Presence of known Claude Code instruction sections
Changes:
- Add claude_system_prompt.go with extracted Claude Code v2.1.63 system prompt
sections (intro, system instructions, doing tasks, tone & style, output efficiency)
- Rewrite checkSystemInstructionsWithSigningMode to build 5 system blocks:
[0] billing header (no cache_control)
[1] agent identifier (cache_control: ephemeral, scope=org)
[2] core intro prompt (cache_control: ephemeral, scope=global)
[3] system instructions (no cache_control)
[4] doing tasks (no cache_control)
- Third-party client system instructions still moved to first user message
Follow-up to 69b950db4c
Three changes to avoid Anthropic's content-based system prompt validation:
1. Fix identity prefix: Use 'You are Claude Code, Anthropic's official CLI
for Claude.' instead of the SDK agent prefix, matching real Claude Code.
2. Move user system instructions to user message: Only keep billing header +
identity prefix in system[] array. User system instructions are prepended
to the first user message as <system-reminder> blocks.
3. Enable cch signing for OAuth tokens by default: The xxHash64 cch integrity
check was previously gated behind experimentalCCHSigning config flag.
Now automatically enabled when using OAuth tokens.
Related: router-for-me/CLIProxyAPI#2599
ensureAmpSignature injects signature:"" into tool_use blocks so the
Amp TUI does not crash on P.signature.length. when Amp sends the
conversation back, Claude rejects the extra field with 400:
tool_use.signature: Extra inputs are not permitted
strip the proxy-injected signature from tool_use blocks in
SanitizeAmpRequestBody before forwarding to the upstream API.
Added comprehensive tests to ensure key order is maintained when modifying payloads in `normalizeCacheControlTTL` and `enforceCacheControlLimit` functions. Removed unused helper functions and refactored implementations for better readability and efficiency.
Added comprehensive support for resolving proxy URLs from configuration based on API key and provider attributes. Introduced new helper functions and extended the test suite to validate fallback mechanisms and compatibility cases.
Added Poixe AI sponsorship information, including referral bonuses and platform capabilities, to README files in English, Japanese, and Chinese. Updated assets to include Poixe AI logo.
Introduce `StartAntigravityVersionUpdater` to periodically refresh the cached Antigravity version using a non-blocking background process. Updated main server flow to initialize the updater.
Fetch the latest version from the antigravity auto-updater releases
endpoint and cache it for 6 hours. Falls back to 1.21.9 if the API
is unreachable or returns unexpected data.
The review asked for the builtin tool registry helper to live with the rest
of executor support utilities. This moves the registry code into the helps
package, exports the minimal surface executor needs, and keeps behavior tests
with the executor while leaving registry-focused checks with the helper.
Constraint: Requested layout keeps executor helper utilities centralized under internal/runtime/executor/helps
Rejected: Keep the files in executor and reply with rationale | conflicts with requested package organization
Confidence: high
Scope-risk: narrow
Reversibility: clean
Directive: Keep executor behavior tests near applyClaudeToolPrefix and keep pure registry tests in helps
Tested: go test ./internal/runtime/executor/helps ./internal/runtime/executor -run 'Claude|Builtin|Tool'; go test ./test/...; go test ./...
Not-tested: End-to-end Claude Code direct-connect/session runtime behavior
