openwork-server: no-op provider patch still reloads the engine (#3307 guard ineffective in production)

[benjaminshafii]

#3307 added a guard so an identical PATCH /runtime-config/providers skips the engine reload. Measured on the real openwork-0.18.11 image, it does not work.

Evidence (live sandbox, server 0.18.11)

before: disposals=3 cfg=1785363765841/4960 sha=1b1e31152dbf
identical PATCH: changed=false reload="reloaded"
after:  disposals=4 cfg=1785363796180/4960 sha=1b1e31152dbf

• The config file is byte-identical before and after (sha=1b1e31152dbf), only mtime moved.
• changed=false, so the DB row was unchanged — therefore fileResult.changed must be returning true.
• The engine disposed anyway (disposals 3 -> 4), which is what aborts in-flight agent runs.

The running binary really does contain the #3307 code, so this is not a stale image:

shouldReload = result.changed || fileResult.changed;
if (shouldReload) { await reloadOpencodeEngine(...) }
reload: shouldReload ? "reloaded" : "skipped"

Where to look

writeOpenworkRuntimeConfigFile in apps/server/src/openwork-runtime-config.ts compares await readFile(path, "utf8") against await buildOpenworkRuntimeConfig(...) and returns changed: false when equal. That comparison is evidently not matching even though the bytes it writes equal the bytes already on disk. Candidate causes not yet excluded: the compared serialization differing from the written one, a second writer alternating content between samples, or the write queue racing itself (fileWriteQueue).

Its unit tests pass, so a regression test must reproduce this against a real file, not a mocked FS.

Severity

Defence-in-depth only. #3301 stopped den-api sending redundant patches, which is what caused the production incident (991 engine disposals, agent runs aborted mid-tool-call, SSE dropped). This guard is the backstop so no future caller can cause it again.

Repro

With a host token inside a cloud sandbox: GET /runtime-config/providers, then PATCH that exact payload back, and watch grep -c 'disposing instance' in ~/.local/share/opencode/log/opencode.log plus the sha of /tmp/openwork-data/runtime-opencode-config.json.

[aimeemccardiewoodplc-maker]

Wow, looking forward for more