Review found the contract documented but not implemented, and one client path
missed entirely.
AsyncMemoryClient's custom-client branch still carried the old literal header
dict, so `AsyncMemoryClient(client=...)` sent no surface identity at all — the
exact asymmetry this work set out to remove.
Both custom-client branches also used a blanket headers.update(), which
overwrites. That is the one code path where an outer layer's identity can
physically be present, and it was the one path that erased it. They now
check-then-set the identity headers and append to an existing client stack,
which is what set-once and append-only were supposed to mean.
AGENTS.md claimed a plugin calling the Python SDK produces
`mem0-plugin/0.3.1, mem0-python/2.0.19`. Nothing in the repo sets the env vars
that would make that happen, so the concatenation was unreachable. Replaced with
the three ways an integration can actually declare itself, in preference order.
memory_core's comment said the backend reads X-Mem0-Source. That is only true
from the platform release shipping alongside this, and a reader would otherwise
trust it and build header-only attribution that silently does nothing — which is
how vercel-ai-sdk was written in the first cut. Corrected in all seven copies,
and the body value is what makes attribution work against either backend.
mem0-ts hardcoded SDK_VERSION = "3.1.8" while the repo already injects
__MEM0_SDK_VERSION__ via tsup, the same mechanism telemetry.ts uses. The
hardcode was correct only until the next release bump.
Dropped both `as never` casts in pi-agent. They suppressed an excess-property
error but also disabled checking of every other option at those call sites, so a
typo in filters or threshold would have compiled. SearchMemoryOptions now
declares `source` instead.
Stack truncation cut mid-identifier, leaving a fragment that parses as a real
client name. It now drops whole entries.
Claude-Session: https://claude.ai/code/session_01C7tEmH86HAr7GoAAKCEHZb
Two defects, one cause: the spool protocol infers ownership instead of holding
it, and never records progress.
Duplicate delivery after a partial failure. flush() posts the claim in batches of
100 and returns on the first failure, keeping the whole file. The retry then
posts every batch again, including the ones that already arrived — 150 recorded
events were delivered 250 times. Progress is now written back to the claim after
each successful batch, so a retry resumes where the send stopped and a crash
repeats at most one batch.
Duplicate delivery when two senders overlap. spool.replace(claim) is os.rename,
which preserves mtime, so a claim created after a quiet minute inherited the
spool's last-write time and looked abandoned the instant it existed. A second
sender starting while the first was still posting took it over and sent it too —
most likely at session end, when the MCP server's exit sender and the SessionEnd
flush worker both drain. Claims are now touched at claim time, and the per-batch
rewrite doubles as a lease heartbeat. _post makes one attempt with SEND_TIMEOUT
and no retry, so a heartbeat lands well inside the 120s lease; a test asserts
that margin so adding a retry loop to _post cannot silently break it.
Parked batches starved. _claim_spool only looked at parked .sending files when
no spool existed, and because sessions keep recording there usually was one — so
a batch parked by a failed send waited until the 7-day expiry deleted it unsent,
despite its own presence being what starts the sender in the first place.
flush() now drains the live spool and then parked claims in the same run, oldest
first, bounded. Expiry applies only after a genuine retry has failed, with the
attempt count carried in the filename.
A sender that gives up releases its lease rather than heartbeating on the way
out, so the next run picks the batch up promptly instead of waiting a full stale
window for a batch nobody is working on. A failing send stops the run, so one
broken connection cannot burn every parked batch's attempt budget at once.
Two existing tests asserted the old lifecycle and are updated in place, each
with a comment saying what changed.
Claude-Session: https://claude.ai/code/session_01C7tEmH86HAr7GoAAKCEHZb
harness is set when an event is recorded; source was set when its batch was
sent. Both came from module globals that stay at "generic" and "MEM0_PLUGIN"
until telemetry.init() runs, and two processes in the pipeline never run it:
- `python3 telemetry.py`, the detached sender spawn_flush() starts at session
start, after every skill command, and when the MCP server exits. Everything it
delivered was labelled source=MEM0_PLUGIN. Only batches flush_worker.py
happened to drain got the real host.
- mcp_server.py, which records every manual search as harness=generic.
All six Python plugins ship the same files, so source could not tell any of them
apart and MCP searches from every plugin landed in one generic bucket. The
portable plugin is worse: it has no flush_worker at all, so its only sender is
the uninitialised one and 100% of its events were mislabelled.
Two changes. record() stamps source beside harness, so the sending process stops
mattering — flush() already spreads per-event properties last, so a per-event
source wins over any sender default. And the build generates core/_harness_id.py
per host, seeding both modules at import, so identity no longer depends on an
entrypoint remembering to call init(). The build already computed HARNESS_ID and
spent it only on skill templating, and bundle_drift already diffs core/
byte-for-byte, so --check catches drift for free.
Deliberately not adding MEM0_PLUGIN_HARNESS to the six manifests: they sit
outside the --sync and --check boundary, which is the property that caused this.
Also unifies two defaults that disagreed. configure_harness derived
`<host>_plugin` while telemetry.init derived `MEM0_<HOST>_PLUGIN`, so a third
value existed. It was unreachable only because hook_runner never calls flush();
moving source into record() would have made it live.
Events now carry a uuid so a resend can be collapsed.
The suite stayed green through all of this because the only tests live under one
host, behind a conftest that calls init() at import. New tests run in real
subprocesses with no init, and cover the portable plugin, which would pass a
native-only test vacuously.
Claude-Session: https://claude.ai/code/session_01C7tEmH86HAr7GoAAKCEHZb
Saket Aryan