fix(github-copilot): preserve reasoning IDs for Copilot Codex models (#71684)

* fix(github-copilot): preserve all reasoning IDs and add gpt-5.3-codex support

The existing guard (8fd15ed0e5) only skipped rewriting reasoning item IDs
when encrypted_content was a non-null string. When gpt-5.3-codex is used
via GitHub Copilot, the model falls through to the forward-compat catch-all
with reasoning:false, so encrypted_content is never requested and arrives
as null — bypassing the guard and causing a rewrite. Copilot validates
reasoning item IDs server-side regardless of whether the client includes
encrypted_content, so the rewritten id triggers the 400 error.

Two changes:

1. connection-bound-ids.ts: skip ALL reasoning items unconditionally.
   Reasoning items always reference server-side state bound to their
   original ID; rewriting any of them breaks Copilot's lookup.

2. models.ts + index.ts: extend the forward-compat cloning logic to
   cover gpt-5.3-codex (adds it to the template-target set and to
   CODEX_TEMPLATE_MODEL_IDS so it can also serve as a template source
   for gpt-5.4). Adds gpt-5.3-codex to COPILOT_XHIGH_MODEL_IDS for
   the thinking profile.

Thanks @InvalidPandaa.

* docs(github-copilot): clarify gpt-5.3-codex is a no-op template for itself

https://claude.ai/code/session_01EAFmq4WyKkiUkVAqRXp4Bm

* fix(github-copilot): remove dead reasoning prefix branch in deriveReplacementId

https://claude.ai/code/session_01EAFmq4WyKkiUkVAqRXp4Bm

* fix(github-copilot): align reasoning id replay tests

* test(plugin-sdk): use cjs sidecar for require fast path

---------

Co-authored-by: Claude <noreply@anthropic.com>
Co-authored-by: Peter Steinberger <steipete@gmail.com>
This commit is contained in:
InvalidPanda ツ
2026-04-25 21:52:07 +02:00
committed by GitHub
parent 1d49b8cdaa
commit b64bfc5d9a
8 changed files with 101 additions and 36 deletions

View File

@@ -18,7 +18,7 @@ function looksLikeConnectionBoundId(id: string): boolean {
}
function deriveReplacementId(type: string | undefined, originalId: string): string {
const prefix = type === "reasoning" ? "rs" : type === "function_call" ? "fc" : "msg";
const prefix = type === "function_call" ? "fc" : "msg";
const hex = createHash("sha256").update(originalId).digest("hex").slice(0, 16);
return `${prefix}_${hex}`;
}
@@ -35,7 +35,11 @@ export function rewriteCopilotConnectionBoundResponseIds(input: unknown): boolea
if (typeof id !== "string" || id.length === 0) {
continue;
}
if (item.type === "reasoning" && typeof item.encrypted_content === "string") {
// Reasoning items always reference server-side encrypted state bound to the
// original item ID. Rewriting the ID — even when encrypted_content is absent
// or null — breaks Copilot's server-side lookup and causes a 400 validation
// failure regardless of whether the client included encrypted_content.
if (item.type === "reasoning") {
continue;
}
if (looksLikeConnectionBoundId(id)) {