Omar SobhandClaude Opus 5
b31a79f650
On the OAuth path Anthropic requires the Claude Code identity to be its own
first system BLOCK. We concatenated it with the caller's prompt into a single
string, so EVERY server-side call that set a system prompt was rejected — and
the rejection arrives as `429 {"type":"rate_limit_error","message":"Error"}`,
which reads as throttling and is not.
Measured on one token, seconds apart:
"PREAMBLE" (string) -> 200
"PREAMBLE\n\nJudge the …" (string) -> 429
"PREAMBLE" (string) -> 200 (control)
["PREAMBLE"] (blocks) -> 200
["PREAMBLE", "Judge the …"] (blocks) -> 200
while the account reported `5h utilization 0.07, 7d 0.11, overage 0.0`, every
window `allowed`. A Max 20x subscription at 7% was being read as out of
capacity.
What this was breaking, silently, for as long as it has been there:
- every `done_when` verdict on the subscription judge. Mission 01a00bbb
pass 2 returned "could not evaluate the completion condition this pass"
and BURNED one of the phase's three passes on it.
- the boot preflight, which reported `claude-opus-4-8 throttled (configured,
no capacity now)` on every start — a diagnostic that was itself the bug.
- mission_refiner, phase_summarizer, swarm planning.
The `claude` CLI was unaffected throughout, because it sends its system prompt
as blocks. That divergence is what made this look like an account problem: the
agents worked while everything server-side "throttled".
After the fix the preflight reports opus-5, sonnet-5 and haiku all `ok`.
The API-key path keeps sending a plain string — it never had this constraint.
Co-Authored-By: Claude Opus 5 <[email protected]>