fix(server): bound provider event log records and pass Codex images by path

[rynfar]

Ports two upstream server fixes from T3 Code. Part of upstream integration cycle #650, bounded at upstream 93e04160a0c0dece8a258384d2118a660415a53d.

Sources

Source	Upstream	Outcome
b17cc2ab5d5029f898121798ca19db3288cba616	#12305 bound provider event log records before serialization	Partially adopted
3fd21df62da3191f1abf12a0cd74df6de9ed30a2	#11050 pass Codex image attachments by path to avoid oversized requests	Adopted

Bounded provider event log records

A provider event with a cyclic reference, a pathological nesting depth or a very large payload could previously drive unbounded traversal inside the NDJSON logger's serialization, and an event that serialized successfully was written at whatever size it happened to be.

boundProviderEventForLogging now walks a record before encoding it, with a 64 KiB character budget, a 1,024 field budget, a depth cap of 16 and a WeakSet ancestor check. Records that fit are written unchanged. Records that do not fall back to summarizeProviderEvent, which keeps routing and failure fields — provider, method, ids, status, error and stop reasons — while replacing long strings with { omittedCharacters } and arrays with { itemCount }. Escaping can still expand a bounded record past the budget, so serialization is re-checked by byte length and falls back to the summary a second time.

Also suppresses three more high-volume transient frames: turn/diff/updated, message.part.delta and Anthropic stream_event / content_block_delta.

Pylon's commitGuard on makeEventNdjsonLogStore.write and Pylon's existing transient filters for claude/stream_event/content_block_delta/, session/update and message.part.updated are preserved.

Excluded: raw-frame suppression

Upstream's change also drops native frames whose envelope carries stage: "raw", and unwraps stage: "decoded" payloads. That part is deliberately not ported.

Two reasons, both verified against this tree rather than assumed:

• The guard is inert here. apps/server/src/provider/acp/AcpNativeLogging.ts writes protocol records as { observedAt, event: { …, payload: { direction, stage, payload } } }. Upstream reads envelope.stage, one level above where Pylon's stage actually sits, so the branch never fires. GrokSkills.ts is the only other stage emitter and its values are spawn/timeout/exit/decode.
• The intent is wrong for Pylon even if it did fire. Upstream's rationale is that raw frames duplicate every token delta. Pylon's do not — formatProtocolLogPayload already reduces the payload through summarizePayload to { valueType, byteLength }, and protocol logging is only attached under verboseProtocolLogging, an explicit opt-in. Those records are the evidence that survives when a frame fails to decode or a response never arrives, which is the Antigravity ACP session/prompt hang signature behind feat: add ACP prompt liveness and truthful forced stops #609.

Revisit trigger: Pylon moves stage to the envelope level in AcpNativeLogging.ts, or ACP raw frames begin carrying unsummarized payloads.

Codex image attachments by path

Image attachments were read from disk and inlined into turn/start as a base64 data URL, so the JSON-RPC request grew with the file. They are now passed as { type: "localImage", path } and the CLI reads the file itself. localImage is a real content type in packages/effect-codex-app-server/src/_generated/schema.gen.ts, so this is protocol-valid rather than a hopeful rename.

Pylon's attachment-id validation against serverConfig.attachmentsDir still runs before the path is returned, so a path outside the attachment store is still rejected. Unlike upstream, FileSystem.FileSystem stays wired into makeCodexAdapter — Pylon's makeCodexSessionRuntime still requires it.

Behavior change worth noting

A circular or oversized event previously produced a SchemaError diagnostic and no log line; it now produces a bounded summary line. The existing Pylon test asserting the SchemaError path was replaced by one asserting the summary path, and it keeps the original assertion that the event's contents never reach the diagnostics. Summarization only narrows what is written — events under budget are unaffected.

Verification

Run on the final head, not taken from a report:

• vp test run apps/server/src/provider/Layers/EventNdjsonLogger.test.ts apps/server/src/provider/Layers/CodexAdapter.test.ts apps/server/src/provider/Layers/CodexSessionRuntime.test.ts — 3 files, 133 tests passed.
• vp run -F t3 typecheck — exit 0.
• vp check on the six changed files — formatting and lint clean.

Backend-only; no client evidence required.

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Thread transfer impact

✅ Thread transfer remains within every enforced ceiling.

Provider	Metric	Main baseline	This PR	Impact	PR ceiling
Codex	Total thread wire	14.0 KiB	13.9 KiB	−45 B (−0.3%)	15.1 KiB	✅
Codex	Thread snapshot wire	7.2 KiB	7.2 KiB	−7 B (−0.1%)	7.3 KiB	✅
Codex	Live turn WebSocket wire	6.8 KiB	6.7 KiB	−38 B (−0.5%)	7.8 KiB	✅
Codex	Live turn WebSocket decoded	58.0 KiB	58.0 KiB	−44 B (−0.1%)	66.4 KiB	✅
Codex	Live turn messages	10	9	−1 (−10.0%)	21	✅
Claude	Total thread wire	14.0 KiB	14.0 KiB	−28 B (−0.2%)	15.1 KiB	✅
Claude	Thread snapshot wire	7.2 KiB	7.2 KiB	+10 B (+0.1%)	7.3 KiB	✅
Claude	Live turn WebSocket wire	6.8 KiB	6.7 KiB	−38 B (−0.5%)	7.8 KiB	✅
Claude	Live turn WebSocket decoded	58.9 KiB	58.9 KiB	−44 B (−0.1%)	66.4 KiB	✅
Claude	Live turn messages	10	9	−1 (−10.0%)	21	✅

Baseline: 933d6f7 · PR result: 2a3bfa0 · Source CI: success

Scenario and decoded snapshot size

10 historical turns, 5 command tools per turn, 878.9 KiB retained MCP result per historical turn, and a 1.05 MiB retained result in the measured turn.

• Codex decoded thread snapshot: 115.6 KiB
• Claude decoded thread snapshot: 116.4 KiB

Updated in place by a trusted workflow. PR artifacts are strictly validated and never executed.