This issue surfaced only because someone ran a slow suite that is
excluded by default and had not been run for eighteen days. As a column
it becomes a query: which model stopped being observable, and when.
The emitter unwraps the enum to a plain str at the single _record exit.
asyncpg makes no promise about encoding a str subclass, and a telemetry
write that fails is downgraded to one warning — it would not crash, it
would just quietly cost the Postgres path a column. Normalising at the
emitter follows what tenant_id, meta and sampling already do.
The column is appended last in COLUMNS and in both DDLs. An existing
table can only take ALTER at the end, so putting it anywhere else
forks the physical column order between a freshly built database and a
backfilled one.
asdict keeps the enum and json.dumps writes it as a string because
StrEnum is a str subclass, but nothing turns it back on the way in, so
a cache hit returned a plain str where the annotation promised an enum.
Verified end to end rather than assumed from the subclass relation.
A value outside the domain now raises inside the existing guard and the
call falls back to source, which is the right direction for a poisoned
or stale cache entry. Entries written before this column existed still
replay: the guard checks for the key first, and a test pins that, since
turning it into an unconditional conversion would quietly turn every
pre-upgrade entry into a permanent miss.
The M3 evidence sat at 08-02 for twenty-three days while nobody could
tell whether it still held. A declaration that goes stale in silence is
the failure this issue is really about, so the library now compares
what it declared against what it just observed and says so when the two
part ways.
Judgement is separated from logging: reconcile_thinking returns the
warning text, so tests assert on the text instead of parsing logs.
Two cases that look alike are kept apart — a model whose capability is
registered gets a drift warning quoting its evidence, an unregistered
one is never told the table said anything, because it never did.
False x UNKNOWN stays silent on purpose. UNKNOWN cannot falsify
anything, and warning on it would fire on every disabled call M3 makes
over the plain endpoint. A warning that always fires is not a warning.
Both assembly paths fill it, streaming and non-streaming alike. Filling
only one is exactly the divergence this issue exposed: M3 returns
reasoning prose over SSE and nothing at all over the plain endpoint, so
a verdict computed on one path says nothing about the other.
The field defaults to UNKNOWN on both TransportResult and LLMResponse.
A transport that does not judge should not get to declare absence on
the provider's behalf, and a default that stays silent is the only one
that cannot lie.
providers.py had been holding two jobs: the registry of what each
provider looks like, and the decisions made from those declarations.
Adding response-side judgement would have made it the module for
everything about reasoning, so the decisions move to thinking.py and
the registry keeps only profiles and their lookup.
Moving a module breaks any deep-path import of what moved, so the six
public symbols are promoted to the package root at the same time. The
top level is this library's stated API surface; giving downstream a
stable name to import is what makes the next reorganisation harmless.
observe_thinking stays unexported — downstream reads the verdict off
LLMResponse, and exporting it would be a permanent promise for nothing.
reasoning_tokens=None has been carrying two meanings at once, no
reasoning and no report, and the library resolved the ambiguity by
quietly claiming the first. ThinkingObservation splits them: UNKNOWN
says the call left no signal, ABSENT says the provider reported zero.
The verdict ranks evidence by hardness. Reasoning prose is the fact
itself; reasoning_tokens is a report about the fact, so a missing
report cannot overrule prose that is right there. The prose check
strips first, since a gateway that returns whitespace is not evidence.
The enum lives in types.py, not in the new thinking.py, because
LLMResponse is typed on it and the innermost layer must not import a
decision module.
client.telemetry_status exists so downstream can reconcile telemetry
programmatically, but annotating its return type meant reaching into
polygateway.types while the convention here is that the top-level
exports are the public API surface. The port itself stays unexported:
nobody outside the library implements it.
The status snapshot reports elapsed time, so asserting retry_after_s
against the real monotonic clock was really asserting that a few lines
of code take zero time; it failed at 59.99993 vs 60.0. The recorder
already accepts an injected clock for exactly this reason.
The pool exhaustion in issue #15 was fatal only because min_size=10 forced
a transient error to surface at pool creation, and that step was hardcoded
to permanent death. Step is the wrong axis: it conflates "the DSN cannot
be parsed" with "someone else holds all the connections right now".
Failures are now classified by two rules. Fatal means the cause lies
entirely inside this process and cannot change, which only the
construction-time DSN satisfies. Everything else splits on whether the
failure has anything to do with this row's data: row-level failures drop
one row and keep trying, environment-level failures cool down for 60s and
then get exactly one retry, so a restarted database or a DBA creating the
table heals on its own.
42703 (missing column) is the single named exception and stays row-level
even though every row fails alike: issue #13 promised that the manual mode
trims the INSERT and exposes drift per row, and that promise outranks the
rule. Any future exception owes the same argument.
The _failed boolean is gone; the tracker is the only degradation state,
because two copies of the same fact drift apart. Closing stays outside
that state: it is the caller's own decision, not an anomaly to recover
from, so the snapshot reports it through dropped_rows and the drop reason
instead of raising the degraded flag on every clean shutdown.
Closing was the last unbounded wait on the shutdown path: asyncpg's
Pool.close() awaits wait_until_released() on every holder, so a single
in-flight connection parks the caller forever (60s only buys a warning).
It now runs under asyncio.wait_for and terminates the pool on timeout;
external cancellation still propagates untouched.
Closing is also final now. Clearing _pool used to leave the recorder free
to build a fresh pool on the next write - worse in the injected case,
where the owner believes it still holds every connection while the
recorder quietly opened its own. Recovery is a runtime concern (cooldown
retry), not a side effect of shutdown, so writes after aclose short out
and count the dropped row with a reason of their own.
Also covers the release/terminate fallback left untested by the pool
work: the fake pool needed for the close cases makes it nearly free.
The pool was the only external resource in the library that pre-allocated:
asyncpg's default min_size=10 turned pool creation into an all-or-nothing
action, so on a shared instance running low on connection budget the first
thing to fall over was the one component that must not fail silently
(4 clients x 10 = 40 idle connections just to write telemetry).
min_size=0 means "do not pre-connect" - asyncpg only builds holders - so
pool creation becomes free and never touches the database; connection
failures then land on acquire, the path that already drops one row and lets
the pool recover. max_size and the write budget become the library's
explicit statement about its own footprint, configurable through two new
keys whose defaults live in config alone (the recorder parameters are
required keyword-only, same discipline as auto_migrate).
The whole write - prepare, acquire, execute - now runs inside one
asyncio.timeout: acquire used to have no timeout at all, so a full pool
would hang forever on the caller's path. Release is explicit rather than
`async with`, because asyncpg shields release and reuses the acquire
timeout, which would let a single telemetry write consume twice the budget.
Telemetry degradation used to be a single warning and a private boolean.
In a long-running process that is indistinguishable from telemetry working:
issue #15 was only found by hand-reconciling milestone log lines against
llm_calls rows, after 19 calls had silently gone unrecorded. The SQLite
side was worse — once init failed, every write returned without even a
log line.
Degradation now has one shared owner. TelemetryStatusTracker holds the
state machine (enter/recover/drop/should-retry), announces entry and
recovery once each, and repeats the drop count under a row-and-time
double threshold so a degraded backend neither floods the log nor goes
quiet. Both recorders hold one; both count the rows they drop.
For programmatic consumers, TelemetryStatus is a frozen snapshot exposed
as telemetry_status on all three clients, resolved through a single
isinstance check. It is a separate optional port rather than a member of
TelemetryRecorder: that protocol is @runtime_checkable, so adding an
attribute would make every implementation that only defines
record_llm_call stop satisfying it — downstream isinstance assertions
would break on upgrade. The existing assertion in test_ports.py is what
keeps that decision honest.
Failure criteria are deliberately untouched here: Postgres still treats a
pool failure as permanent, only now visibly. `_failed` and the tracker
therefore both carry the verdict for the span of this one change; the
cooldown rework collapses them into the tracker alone.
A client used to close whatever transport, recorder or cache it happened
to hold, injected or not, so the first client to shut down killed the
backend its siblings were still using. That is why the explicit-sharing
path the architecture prescribes was unusable in practice and downstream
projects fell back to one private instance per client. The mirror image
of the same gap: the redis clients the factories build for the limiter
and the breaker were never closed at all, because nobody kept a
reference to them once they were handed to the retry middleware.
Ownership is now stated once, the way RedisLimiter already stated it:
whoever builds a resource closes it, injected ones are left alone. The
constructor is the full-injection path, so it owns nothing by default
and only the factories mark what they built. RedisCache gains the same
rule for its own client, and the three copies of the "probe for aclose,
fall back to close" dance collapse into a single helper so the next
correction cannot land in only one of them.
Branch review caught the docs claiming something the code does not do.
CHANGELOG, README and the design's behaviour matrix all said a
force-opened source under circuit_open=wait waits out the full stall
window. It does not: the probe let through after each cooldown is a
real attempt, so it burns a max_attempts slot like any other, and a
401 source usually runs out of retry budget first -- reason is
retry_exhausted, not stalled. Which budget wins depends on
max_attempts against the cooldowns and the stall window.
The behaviour is right; only the prose was wrong. Charging the probe
to the retry budget is exactly the split issue #8 settled: the
question is who spends max_attempts, and a probe does send a real
request. A test now pins it so the claim cannot drift again.
Also drops the planned "woke up" log line. Each wait round already
logs on entry with its duration, and a still-blocked wake-up logs the
next round immediately, so a second line would only double the volume.
on_no_runnable now dispatches on why every source was rejected instead
of falling through two serial branches. Under wait, a fully open circuit
sleeps out the cooldown and comes back for another round; the breaker's
protection is untouched (still not a single request leaves during the
wait, so no quota or money burns) -- what changes is whether the caller
dies on the spot or queues.
Dispatching is not cosmetic. Left serial, wait would fall into the quota
branch and a caller with quota_full=fail_fast would get a
quota_exhausted error while its quota was in fact fine.
_nap sleeps to the cooldown deadline rather than polling every 10ms,
which for a 60s cooldown is 6000 round trips per in-flight call on the
Redis backend. Jitter is added on top instead of scaling the wait, since
waking early before a known deadline just earns another rejection. Both
arms clamp to the remaining stall budget, so the worst case per call is
stall_window plus one poll and does not drift with max_cooldown_s. The
clamp's lower bound is the jitter itself, not poll_interval -- the
latter would have lifted the existing [0.5p, 1.0p] quota polling.
Limiter rejections have always chosen between waiting and failing fast;
breaker rejections had no such choice. The new key is the missing cell
of that matrix, shaped exactly like QUOTA_FULL so there is nothing new
to learn. It defaults to fail_fast: flipping the default would move
every existing deployment's worst-case wall clock from milliseconds to
the stall window, which is the wrong direction to impose on anyone.
Single-source scopes are the ones that want wait, and they now have a
way to say so.
The two keys stay separate despite sharing a domain, because a full
quota is "queue for your share" (your turn always comes) while an open
circuit is "wait for the source to recover" (it might not).
Policy validation collapses into SourceAdmission, the only consumer.
The three client constructors used to each carry their own copy of the
quota_full check; adding a second key there would have made eight
copies of the same two lines. Rejection timing and message are
unchanged -- admission is built inside those constructors.
This commit only wires the key through; the control flow that reads it
lands next.
_pick_runnable and _on_no_runnable lived in three copies (retry.py,
embedding.py, ocr.py), the latter two being verbatim subsets of the
first. Admission semantics keep evolving -- issue #8 changed the stall
accounting, M2.5 added the AIMD pacer, issue #14 is about to add a wait
policy -- and every round had to be applied three times.
SourceAdmission now owns picking a runnable source and deciding what
happens when none is available. The three loops keep their QuotaGate,
BreakerGate and pacer references because _attempt still needs them for
write-back and pacer.leave(); those instances are shared, not rebuilt
(a second pacer would split the in-flight counter). The cooldown memo
moves in wholesale since only admission consumes it.
Behaviour is unchanged: pick differs from the old chat copy only by the
pacer None-guards, on_no_runnable is verbatim identical, and the suite
reports the same 967 passed / 21 skipped / 32 deselected as before. The
one visible change is the settle-and-release warning text, which had
three variants ("permit", "embedding permit", "OCR permit") and is now
one. Tests importing _demote_call_failures follow it to its new home.
The library only ever SELECTs/INSERTs into llm_calls (D15), so expiring
rows has to live outside it — holding DELETE would contradict the
REVOKE UPDATE, DELETE the deployment template recommends.
tools/telemetry_retention.py is dry-run by default and prints the row
count, the created_at window and the tenant_id spread so an operator can
tell whether the rows about to go are the intended ones. The Postgres
branch refuses partitioned targets with exit code 3 (DETACH/DROP
PARTITION is O(1); DELETE is not) and otherwise deletes in per-batch
transactions. Missing asyncpg exits 2 rather than degrading quietly:
this is an ops tool, and a silent "0 rows" reads as "already clean".
Exit codes are the contract with the scheduler, so argparse errors were
moved off 2 (now 1) to keep "bad flags" distinguishable from "cannot
reach the database".
The Postgres cases run against the real instance in throwaway schemas —
never public.llm_calls — and the batch case asserts the shared table's
row count is unchanged, so a search_path that failed to apply lands as a
red test instead of a deletion.
`PGW_TELEMETRY_TEXT_CAP` now reaches the emitter on every assembly path.
Unset means no truncation, which stays the default: a truncated row is
no longer audit evidence and cannot be replayed, and downstreams rely on
that today. The flip side — contracts and bids sitting in `llm_calls`
indefinitely, multi-tenant — is spelled out in `.env.example` so readers
can weigh both.
All three `from_settings` paths are wired (chat, embedding, OCR): they
write the same table, so capping only chat would leave half of it
uncontrolled. `TelemetryEmitter.__init__` now rejects `text_cap <= 0`;
it is the single point where the three clients converge, so the direct
construction path — a public assembly route the settings guard never
sees — is covered too. `0` would otherwise reduce every body to a bare
elision marker.
Chat rows stored full message and response text with no upper bound, so
downstream contracts and tenders lived in llm_calls indefinitely. Add
_cap_text/_cap_messages in the single telemetry exit (_record), applied
after digest_messages and before json.dumps, plus to response/thinking.
Capping is per text, not over the serialized JSON: cutting the whole
string would emit invalid JSON into an unvalidated TEXT column. The cap
builds new dicts and never mutates in place — digest_messages passes
non-list content straight through as the same object, so an in-place cut
would silently poison the caller's messages and the cache key.
text_cap is required on TelemetryEmitter (internal class, three known
construction sites) and defaults to None on the three public clients, so
the default behaviour stays byte-for-byte identical. Settings wiring
lands separately.
PG requires a partitioned table's unique constraints to include the
partition key, so issue #12's RANGE partitioning on created_at forces
the primary key to (call_id, created_at). The old
`ON CONFLICT (call_id) DO NOTHING` then matches no constraint and PG
rejects every row with
there is no unique or exclusion constraint matching the
ON CONFLICT specification
which the recorder swallows as a per-row warning: telemetry would go
silently dark under a partitioned deployment. The target-free form is
valid on both table shapes and is literally equivalent on a plain table
(the primary key is its only unique constraint). SQLite's
`INSERT OR IGNORE` already carries no target and is untouched.
Integration coverage on the real PG instance, both inside self-created
temp schemas: a plain table still keeps one row per call_id, and a
table partitioned by created_at now accepts writes and reads them back.
The second case was red before this change with the error above.
Not related to the schema work. These three fail ruff format --check on
main as well -- the pinned ruff is newer than whatever last formatted
them -- and a red make check makes the per-task quality gate useless for
everything that follows.
DDL, column order and backfill statements lived twice, once in each
recorder. A public telemetry_schema_sql() would have made three copies,
and the drift shows up downstream as "I ran the printed SQL and the
library still reports a missing column".
Move both DDLs, both backfill lists and the 24 INSERT fields into
telemetry/schema.py verbatim; the recorders now import them and build
_INSERT through insert_sql(backend, COLUMNS) at import time. The
generated statements are byte-identical to the previous constants, so
runtime behaviour is unchanged (the postgres conflict target stays
bound to call_id for now).
insert_sql() validates its columns against COLUMNS: from the next task
on those names come from database probing, not from a constant, so the
subset check is the gate on the only injection surface. The new
telemetry_schema_sql() prints a paste-ready migration script; its
postgres backfill deliberately uses ADD COLUMN IF NOT EXISTS while the
library's own statements do not, because that form takes an ACCESS
EXCLUSIVE lock even when the column exists. Both variants are derived
from one declaration list so their column sets cannot drift.
The cache-key test only asserted a hit, so a key degraded to a constant
would still pass it. Adding a namespace control group that must miss
proves the key still distinguishes inputs; verified by degrading
build_cache_key to a constant and watching the case go red.
The allow_nan=False branch had no test at all. A ChatRequest built with
a nan meta value (bypassing the entry validation, i.e. a future entry
point that forgets to validate) must drop the row and not raise;
verified red by removing allow_nan=False.
Also restore the read-only file permissions in a finally block, so a
failing assertion does not get masked by a PermissionError from tmp_path
cleanup; rename the warnings fixture to captured_warnings so it stops
shadowing the stdlib module; and drop a downstream business term from a
fixture value (zero-business-assumption rule).
OcrClient is the third telemetry path that skips the chat onion: _emit
builds its own ChatRequest purely to reuse the shared TelemetryEmitter,
so wiring chat() and embed() alone left every OCR row without a tenant
while those rows land in the same llm_calls table. Take the dimensions
at both public entries, validate them there (anything failing further
down is degraded to a warning), and thread them through _call ->
_attempt -> _emit so success, rejection, cancellation and retryable
failure rows all carry the same pair.
EmbeddingClient does not go through the chat onion: it builds its own
ChatRequest inside _emit purely to reuse the shared TelemetryEmitter, so
wiring chat() alone left every embed row without a tenant. Validate the
dimensions at the embed() entry (before batching, since anything failing
further down is degraded to a warning) and thread them through
_embed_batch -> _attempt -> _emit so every batch row carries the same
pair.
Validation runs before the request enters the onion: every failure inside it
is downgraded to a warning by the telemetry layer, so validating in there
would not validate anything.
The dimensions stay out of the cache key — cache_namespace already carries
tenant isolation, and folding meta in would cold-start every existing entry.
Both telemetry backends gain tenant_id and meta at the end of the
column list, and TelemetryEmitter fills them from the request. The two
halves ship together because the emitter is the only caller of
record_llm_call: adding the columns without filling them leaves every
row short of two keys, and the backends read those keys outside their
try block, so the KeyError degrades to a warning and the whole table
stops filling.
The columns are appended, never inserted. An old table can only gain
columns through ALTER, which puts them last; a new table built from the
DDL would put them wherever the DDL says. Anywhere but the end and the
two paths produce different physical column orders, while the INSERT
uses positional placeholders.
The two backends spell the default differently for different reasons.
SQLite refuses a NOT NULL column without a non-NULL constant default
outright, so the default is what makes the backfill legal at all. On
Postgres a non-volatile constant default is what keeps the ALTER from
rewriting the table, and NOT NULL DEFAULT '' is what keeps old rows out
of the black hole a NULL tenant_id falls into under an RLS policy.
Normalisation happens in the emitter, not the recorder, matching how
canonical_sampling_json already settles the sampling column: None
becomes the empty string, an empty mapping becomes the literal '{}'.
Keys are sorted so one set of dimensions serialises identically on
every row, and allow_nan=False is a second gate behind the entry
validation -- json.dumps would otherwise write a bare NaN, which JSONB
rejects, and the failed insert would be swallowed as a warning.
All three emit entry points read the request. Cache hits read it too,
rather than the replayed response: the dimensions answer who made this
call, not who made the one whose result is being replayed.
Adds validate_caller_dimensions and the two ChatRequest fields that
carry them. Every limit rejects rather than trims: Langfuse drops
metadata values past 200 characters, which leaves the caller believing
something was recorded when nothing was.
Whitespace on tenant_id is refused outright instead of stripped. " t1"
and "t1" compare unequal inside an RLS policy, so silently rewriting the
caller's value would hand them a tenant whose rows they cannot find.
Non-finite floats are refused for a concrete reason: json.dumps writes
them as the bare literals NaN and Infinity, which are not valid JSON and
which JSONB rejects. Letting one through turns a caller's input mistake
into a failed insert, and the telemetry layer degrades failed inserts to
a warning -- so the mistake would surface as missing rows, nowhere else.
The new fields go after sampling so no positional construction of
ChatRequest shifts. Validation is split across three helpers to keep
each one under the complexity gate.
Verifier mutation test: flipping _translate_429 to parse the summary
left all 824 tests green. The padding was one long string value, so the
cut landed inside it - and head-and-tail retention kept the trailing
error object, leaving the summary parseable. Many keys put the cut
between structural tokens, where the summary stops being valid JSON.
Mutation now fails as it should. Also splits OCR 429 out on its own.
Issue #10 Task 4: the OCR side said only 'HTTP 404'. The issue reported
the chat path, but the batch that lost its 400 was reading tables - the
same blind spot, one transport over. Reuses the shared summarizer.
Issue #10 Task 3: five branches each built their own message, so adding
the summary would have meant five copies. Table-driven classification
composes it in one place instead, and the 429 split still parses the
untruncated body - reading the summary would demote an oversized
insufficient_quota to a plain rate limit and stop force_open.
Issue #10 Task 2: head-and-tail rather than a head-only cut, because the
code and request_id that let you chase the provider sit at the very end
of a JSON error body. Cap 2048 follows k8s client-go for the same job.
Issue #10 Task 1: a rejected call's reason had nowhere to live. The
field goes on the base class because these errors all come from one HTTP
response - which class it is and what the peer said are orthogonal.
PostgreSQL checks the schema CREATE privilege before the IF NOT EXISTS
existence test, so an account with only table-level INSERT was denied on
CREATE TABLE IF NOT EXISTS even though the table was right there and
writable. The denial set _failed and the whole recorder went no-op for
the process lifetime, silently: 150+ calls downstream lost their latency,
token and cost rows with nothing but one warning to show for it.
The probe is the direct fix. The larger fix is the criterion: structural
degradation now means "provably cannot write" (pool creation failed, or
the table is absent and cannot be created), not "something threw during
init" -- a probe or acquire failure just skips the row and retries on the
next call.
SQLite stays as it is on purpose. Measured: it short-circuits the
statement at parse time, so it passes even under another connection's
EXCLUSIVE lock or on a read-only file. A probe there would buy nothing;
the docstring now says so to keep symmetry-minded future edits away.
Patch rather than minor: the error surface is unchanged and no public
signature moved. What downstream must notice is timing, not types — the
worst-case call duration rises to roughly max_attempts * timeout_s now
that the retry budget actually applies.
Pre-release review caught an overreaching promise in the changelog entry:
the 429 bound holds only when the stall verdict can fire at all, i.e. when
the whole scope has no progress. The verdict is a conjunction, so a call
does not die while other calls in the scope are still producing — by
design — which leaves no hard per-call ceiling in that case. That property
predates this fix and is now stated with its precondition instead of as an
unconditional guarantee.
The wiki sync in the release checklist is a no-op again: the doc site has
been down since 2026-08-02 and its landing page names CHANGELOG.md as the
version source of truth, which this commit updates.
Independent verification found the first cut had swapped one bug for a
worse one. The budgets were split by "did we send a request", so a 429
attempt counted as productive — but 429 is exempt from the retry budget,
so its time burned neither budget. Against a queueing gateway that holds
the request for the full timeout before answering 429, a call could hang
for 301 attempts / 25.2 hours, measured, versus 301 seconds before the
change.
The split is now by which budget the time consumes: time that burns
max_attempts is excluded from stall, time that does not (429 attempts
included) belongs to stall. Measured again: back to one attempt / 301s.
Only the chat loop needs this — embedding and ocr count 429 against
max_attempts unconditionally, so the gap never existed there. The stall
verdict moved into _stalled(), which both call sites had duplicated, to
keep __call__ under the complexity gate.
The concurrency case used two RetryMW instances, so instance-level sharing
was hidden by object isolation and a clock promoted to an instance
attribute passed all seven cases. Both cases now reuse one mw, and a new
one idles past the window between two calls on that instance — the shape
that would expose _entered_at pinned to process start. Mutation-checked:
promoting the clock fails the new case.
Same failure path as the embedding loop: one timed-out attempt drains the
wall-clock window, and the next round without a runnable source declares
the scope dead in _on_no_runnable. All three governance loops now meter
stall the same way.
The embedding loop shares the wall-clock entered_at and the same stall
verdict, so it failed the same way through a different path: one timed-out
attempt, then any round with no runnable source, and _on_no_runnable
declared the scope dead. Issue #8 only recorded the chat path; the
regression test pins this one.
Issue #8: with timeout_s >= stall_window_s a single timed-out request
exhausted the stall window before the second attempt was even dispatched,
so LLM_MAX_RETRIES never applied and the whole scope was declared dead.
Root cause is that real attempts and non-productive waiting charged the
same wall clock, while the stall budget is the smaller of the two. The new
StallClock subtracts attempt time from the stall account, leaving the two
budgets orthogonal: attempts bill max_attempts, waiting bills
stall_window_s. The dual-condition verdict, the inf semantics of
progress_age_s, the 429 exemption and the error surface are untouched.
The productive boundary is _attempt itself, telemetry included, so a slow
recorder cannot push a call into a stalled verdict.