Exploring Signals scouts
A
scout is a scheduled agent that wakes on its own interval, looks at one PostHog project,
decides what's genuinely worth surfacing, and either emits it as a
finding into the Signals
inbox or closes out empty (a real, valid outcome). PostHog ships a fleet of canonical scouts — a
cross-product generalist (
) plus per-surface specialists (error tracking,
logs, AI observability, experiments, feature flags, session replay, web analytics, surveys, and
more). A project may also have
custom scouts beyond the canonical fleet — any
skill a team authored (e.g.
,
) shows up here
too, so don't assume a fixed roster:
signals-scout-config-list
is the authoritative roster for
a project. (One caveat: a just-authored scout has no config row until the coordinator's next
tick auto-registers one — or until someone registers it via the write-side
signals-scout-config-create
— so a brand-new scout may briefly be missing from the list.)
This skill helps you
understand and explore what a project's scouts are doing and how they're
performing — entirely through read-only MCP tools. It is the observability counterpart to
the
skill (which teaches writing and tuning) and to the
skill (which covers the inbox reports scouts feed into).
There are five things you can observe about the fleet, each with its own tool:
| What you want to know | Tool | What it tells you |
|---|
| Which scouts run, how often, in what posture | signals-scout-config-list
| One row per scout: schedule, , , , |
| What the scouts actually did, run by run | / | Per-run status, timing, end-of-run summary, , deep-link |
| What the fleet has learned across runs | signals-scout-scratchpad-search
| Durable per-team memory (baselines, noise, allowlists) |
| What the scouts actually emitted | over | The authoritative per-finding record (weight, severity, confidence) — see below |
| What the scouts surfaced to the user | | Findings that cleared the bar and became inbox reports |
The orienting sixth is
signals-scout-project-profile-get
— the deterministic snapshot of "what's
true about this project" that every scout cold-starts from. When a scout found nothing, this is
usually why.
Output handling: expect to offload to a file
Two of these tools —
and especially
tasks-runs-session-logs-retrieve
— routinely return payloads that
overflow an MCP client's
token budget and get spilled to a file. This is the normal path, not an error. Plan for it up
front rather than discovering it after a failed call:
- Keep small on (~10–15). Each row carries a long prose
, and runs come back newest-first across the whole fleet, so even a modest page is
large.
- Session logs are large by nature. A single run's log is hundreds of KB to a few MB. Fetch it
with (so the saved file is real JSON, not the pretty text format — -able)
and read the saved file with / a script rather than inline.
- Don't hand-parse the session log. The bundled do the
reconstruction for you — see below.
Start here: is the fleet even set up?
Don't assume the project has scouts. The fleet only runs on teams enrolled via the
feature flag, and a project may have no configs, all-disabled scouts, or scouts stuck in dry-run.
Run this first whenever a user asks about their scouts for the first time in a session.
json
signals-scout-config-list
Read the result against three cases:
The config list is unpaginated — it comes back as
(a bare array), with no
field. Read the result against three cases:
-
Empty () — no scouts are registered. The project isn't enrolled in the scout
fleet (or hasn't ticked yet). Say so plainly; don't go fishing for runs. Point the user at the
Signals scout settings / PostHog Code onboarding rather than inventing activity.
-
Configs exist but all — the fleet is registered but paused. Nothing is
running. Tell the user which scouts exist and that they're all off.
-
At least one — the fleet is registered and that scout is allowed to run. For
each enabled scout note its
(cadence),
(false =
dry-run, runs
but writes nothing to the inbox), and
. One caveat before reporting "it's live": runs
are gated by the
feature flag, not by
. A project that was enrolled and
later drained from the flag keeps its
rows, but the coordinator no longer plans
runs for it — so a stale or
on an enabled scout usually means the project is
no longer enrolled, not that the scout is idle.
is a dispatch stamp, not proof a run executed. The coordinator advances it the
moment it
enqueues a child workflow for a due scout — before any worker picks the run up. Child
dispatch is fire-and-forget, so if workers are saturated or down the children just queue and no
run ever materializes, yet
keeps marching forward each tick. So a recent
means "dispatched this tick,"
not "a run is genuinely happening." The
authoritative liveness signal is the newest actual
run row in
, not
the config stamp. Cross-check them: if
is fresh (minutes ago) but no run row has
appeared for that scout in well over its
, the fleet is
dispatching but
not running — workers backed up / down, or runs stranded — a real reliability problem, not a
live scout. Don't report "it's running" off
alone.
A scout that is
but
is the most common source of "my scout isn't
doing anything" confusion: it
is running and reasoning every tick, it just isn't allowed to post
findings yet. Always surface the
posture when reporting on a scout.
See
references/scout-data-model.md
for every field on a config,
run, and scratchpad entry, the run status values, and how the pieces link together.
Workflow: survey the fleet
"What scouts do I have / what are they doing?" — lead with
, then enrich with the
most recent run per scout so the user sees liveness, not just configuration.
signals-scout-config-list
— the roster.
- For each enabled scout, and pick the newest run with a matching
(runs come back newest-first across the whole fleet, so a single call usually
covers everyone). Report and how long ago it ran.
Present it as a table the user can scan — scout, cadence, posture, last run, last outcome — and
call out anything anomalous (never run, last run errored, stuck in dry-run for a long time).
Workflow: understand one scout end to end
"How does my error-tracking scout work / how is it doing?"
- Read its config — find the row in for
signals-scout-error-tracking
:
schedule, posture, last run.
- Read its body —
posthog:llma-skill-get {"skill_name": "signals-scout-error-tracking"}
returns the team's actual instruction set (which may be a canonical default or a diverged,
hand-edited row). This is what the agent is told to do every run — its signal-vs-noise
discriminator, explore patterns, and disqualifiers. To understand why a scout behaves the
way it does, read its body.
- Read its recent runs — with set to the skill's domain, or just scan the
newest runs and filter to its . The end-of-run on each run is the scout's
own account of what it looked at and decided.
- Read what it remembered — (see below). The memory entries a scout wrote
reveal the baselines and noise it has internalized about this project.
Workflow: read recent runs
returns the most recent runs across the whole fleet, newest first
(capped at 100). Use it to answer "what happened lately?"
- Scope to a window with / (ISO-8601; inclusive lower, exclusive upper
on ). Walk backwards by passing an earlier .
- Search summaries with — a case-insensitive substring match on each run's end-of-run
. This is how the headless scout dedupes, and it's how you find "did any run already
look at the checkout error spike?"
- Filter by emit outcome with — returns only runs that surfaced at
least one finding, only the quiet runs. This is the direct way to answer "which
runs actually emitted something?" without parsing prose.
Each summary row carries
,
,
,
,
,
,
(how many findings the run emitted),
(their
ids),
(a deep-link into the Tasks UI for the full transcript), and the
prose.
Lead with the
when narrating to the user — it's the scout's own plain-language close-out —
and always offer the
for the full reasoning.
Workflow: drill into a single run
When the user wants the full story of one run (or pastes a run id / Tasks URL):
json
signals-scout-runs-retrieve
{ "id": "<uuid>" }
Note the field name flip:
returns each run's id as
, but
takes it as
. Pass the
value through as
.
Returns the full run:
,
/
(compute duration from these),
/
(what ran, at what body version), the end-of-run
,
/
, and
. The transcript — the actual tool calls and
reasoning — lives in the Tasks UI behind
, not in this payload; hand the user that link
when they want to see every step. A
failed run returns an empty
and
no error
field — the payload looks the same as the list row, so to learn
why it failed you need the
transcript.
You don't have to open the UI for that:
tasks-runs-session-logs-retrieve
returns the run's
session log (every tool call, message, and reasoning step) as data — handy when you're
diagnosing a failure or want to trace exactly what a run did without leaving the conversation. Pass
the run's
as
and its
(both are on the run row).
The raw stream is large (hundreds of KB to a few MB) and will overflow inline, so
fetch it with
and let it spill to a file, then run it through
scripts/render_run_report.py
rather than parsing it by hand.
⚠️
Do not reach for exclude_types: "tool_call_update,…"
to slim it down. It is tempting —
the stream is dominated by incremental
chunks — but each tool's
actual input
lives only in those chunks: the base
event carries an empty
, and the
streamed updates build the input (and the final
) token by token. Excluding them leaves
you with tool
names but no idea what the scout actually queried. Fetch the
full log and let
the script reassemble each call (it groups by
, keeps the richest
, and
attaches the completion's
/
).
Whether a run emitted is a first-class field: . means the
run surfaced that many findings;
means it closed out empty. Don't parse the prose
for this any more — a phrase like "already emitted P1 … did not re-emit" describes a
prior run, so substring-matching the summary for "emitted" is unreliable, whereas
is the authoritative tally.
lists the
s behind that count, in emit
order; each maps to a
with
source_id = run:<run_id>:finding:<finding_id>
, giving a
reliable run → finding link. See
references/scout-data-model.md
for the run-to-finding link and how an emitted finding rides through grouping into the
source_product: "signals_scout"
inbox filter.
A run with
complete and an empty-handed summary ("surface at baseline, nothing to
emit") is a
healthy outcome, not a failure — most runs should close out empty. Treat a stream
of empty close-outs as the fleet doing its job, not as the fleet being broken.
Workflow: inspect what the fleet has learned
The scratchpad is the fleet's durable, per-team memory — prose entries scouts write so future
runs get smarter and quieter. Reading it tells you what the fleet believes about this project.
json
signals-scout-scratchpad-search
{ "text": "error_tracking" }
Returns entries newest-first (capped at 100);
matches
and
case-insensitively. Omit
to browse everything. Each entry's
carries a category
prefix that tells you
what kind of learning it is:
| Prefix | Meaning |
|---|
| A baseline — how this team's data normally shapes |
| A live issue being tracked but still below the emit bar |
| A pattern the fleet has decided to ignore (dev-only, single-user…) |
| Something the team fixed or moved on from |
| A gate on re-emitting a specific issue / fingerprint / finding |
| Vetted entities never to re-surface |
| A product/surface this team doesn't use (close-out memo) |
| A tooling gap a scout noticed worth raising later |
This is the common vocabulary, not a closed set — scouts coin their own prefixes and
labels as needed (the live fleet uses
heavily, for example), so treat an unfamiliar
prefix as just another category. Entries cross-reference each other with
wikilinks. Keys
follow
<prefix>:<domain>:<entity>
(e.g.
dedupe:error_tracking:019e8375-…
).
When a user asks "why isn't my scout flagging X anymore?", search the scratchpad for
,
,
, and
entries — the fleet may have deliberately learned to
suppress it. The canonical prefix vocabulary and the four-state dedupe classifier the fleet
reasons in terms of are documented in the
skill
(
references/dedupe-and-memory.md
).
Workflow: list what scouts have actually emitted
"What has the fleet emitted lately / show me every finding my scouts produced." The run row
carries no emit flag and no finding count, the prose
is heuristic, and the inbox
filter (below) is lossy because grouping merges scout findings into mixed-source clusters. The
authoritative per-finding record is the emitted signal itself, in the
table — queryable for any team via
(the general path). When a scout emits,
writes a signal with
source_product="signals_scout"
; the scout's attribution
(
,
,
,
) lands in
, with
and
at the top level.
Fetch with
and format with
scripts/emitted_signals.py
— the
exact query lives in the script's header. One row per finding, filterable by any set of scouts:
bash
# call --json execute-sql { "truncate": false, "query": "<the emitted-signals query>" } -> emitted.txt
python scripts/emitted_signals.py --signals emitted.txt --now <ISO> [--skill mcp-feedback,general]
A row here is
ground truth that a finding persisted — it cleared every emit gate. The flip
side matters when explaining a gap: a scout can narrate "EMITTED ..." in its
yet have
the emit
silently dropped by a preflight gate (dry-run at the time, the org hasn't approved
AI processing, or the
source is disabled), or the emit failed. Those never reach
this table, so a claimed-but-absent finding is itself a diagnostic, not a script bug. The emit
contract behind each row (weight vs. confidence rubrics, severity, dedupe) is documented in the
skill (
references/emit-contract.md
); the run → finding link and its
limits are in
references/scout-data-model.md
.
Workflow: see what scouts have surfaced
Scout findings reach the user as inbox reports. Filter the inbox to the scout source:
json
inbox-reports-list
{ "source_product": "signals_scout", "limit": 20 }
This is the direct way to find scout-backed reports. Each finding is emitted with
source_product="signals_scout"
, that tag rides through grouping into the report's signal metadata,
and the inbox filter keeps any report whose contributing signals include
— so the
result is the set of reports the fleet has surfaced.
An empty result means the fleet hasn't emitted (yet),
not that the filter is broken. Scouts hold
a high bar — most runs close out without emitting — so on a quiet or newly enrolled project zero
scout-backed reports is the normal, expected state. For the per-run view of what emitted, work from
the runs instead:
signals-scout-runs-list?emitted=true
lists every emitting run, and each run's
/
tell you how many and which findings it produced (each
maps to a
with
source_id = run:<run_id>:finding:<finding_id>
). To browse the
inbox more broadly, use the
skill (statuses, suggested reviewers, drilling
into a report's underlying signals). The emit contract behind each finding — weight, confidence,
severity, the description prose — is documented in the
skill
(
references/emit-contract.md
).
Workflow: assess health and performance
"Is my scout actually working / earning its cost?" There's no single metric — judge a scout over a
window of runs. Pull the runs (
with a
), then reason across the dimensions
below. The full playbook, including how to read each signal and the common failure modes, is in
references/assessing-performance.md
.
- Cadence adherence — are runs landing roughly every ? Large gaps mean
the coordinator is skipping it (disabled, drained from the flag, or capped out on busy ticks) —
or it's dispatching but the runs aren't materializing. Tell the two apart with : if
the config's is also stale, the coordinator stopped planning it; if is
fresh but the newest run row is hours old, it's the dispatch-vs-execution divergence above (workers
backed up / down, or runs stranded), which alone hides.
- Success rate — how many runs reach a clean vs. error out? A run of errors is a
broken scout, not a quiet one.
- Emit rate — what fraction of runs emitted vs. closed out empty. Read it straight off
per run (or split the window with / ).
Near-zero over a long window on a live surface can mean the discriminator is too strict (or the
surface really is quiet); near-100% usually means it's too noisy. Most healthy scouts emit rarely.
- Signal-to-noise — of what it emitted, how much became actionable inbox reports vs. got
suppressed? Use each emitting run's to tie runs to their rows, and
cross-check against report states.
- Memory growth — a healthy scout accumulates / / entries over
time. A scout with an empty scratchpad after many runs isn't learning.
Helper scripts
The skill bundles four
pure formatters under
for the most common asks.
They do
no network I/O — they are the back half of an "agent fetches, script formats" split.
The pattern is always the same:
- Fetch each payload with the MCP using (raw JSON, not the pretty text format)
and save it to a file. For the big ones (,
tasks-runs-session-logs-retrieve
) this
is mandatory anyway — they overflow inline and spill to a file you can point the script at.
- Run the script over those files.
All four are stdlib-only Python 3.11+ and print
plain text to stdout (or
) — designed
to read well in a terminal, so save them as
.
scripts/render_run_report.py
— drill into one run
Produces the kind of detailed write-up you'd want when inspecting a single run: header
(status, duration, posture), a narrated timeline that interleaves the agent's narration with
each tool call and its real input, the end-of-run summary, and any scratchpad memory.
bash
# fetch (note --json), saving each to a file:
# call --json signals-scout-runs-retrieve { "id": "<run_id>" } -> run.json
# call --json tasks-runs-session-logs-retrieve { "id": "<task_run_id>", "task_id": "<task_id>", "offset": 0 } -> log.json (FULL — no exclude_types)
# (optional) call --json signals-scout-scratchpad-search { ... } -> mem.json
# (optional) call --json signals-scout-config-list {} -> cfg.json
python scripts/render_run_report.py --run run.json --log log.json \
--scratchpad mem.json --config cfg.json --out report.txt
| Mode | Contains | needed? |
|---|
| header + posture + close-out prose | no |
| + narrated timeline with tool inputs + tool tally + scratchpad | yes |
| + each tool call's (truncated) output inline | yes |
Other flags:
(outputs in detailed mode),
/
(truncation),
(skip the hedgehog banner),
(defaults to
).
— survey the whole fleet
One scannable table — scout, enabled, posture, cadence, last run, last outcome — with a "worth a
look" section that flags never-run, stuck-in-dry-run, and last-run-failed scouts.
bash
# call --json signals-scout-config-list {} -> cfg.json
# (optional) call --json signals-scout-runs-list { "limit": 30 } -> runs.json (small limit!)
python scripts/fleet_survey.py --config cfg.json --runs runs.json --now <current-ISO-time>
Pass
(the current time, ISO-8601) to get relative "ago" columns; the emit/quiet column is
a
heuristic on each run's summary prose — confirm against the summary before trusting it.
— health over a window of runs
Implements the "assess health and performance" workflow above: a per-scout table (runs, success
%, emit %, cadence gap vs interval, adherence, median duration, memory growth) plus a "worth a
look" section flagging all-failed scouts, timeout-shaped failures, cadence stalls, staleness, and
empty scratchpads.
bash
# call --json signals-scout-runs-list { "limit": 100, "date_from": "<ISO>" } -> runs.json
# (optional) call --json signals-scout-config-list {} -> cfg.json
# (optional) call --json signals-scout-scratchpad-search {} -> mem.json
python scripts/assess_health.py --runs runs.json --config cfg.json \
--scratchpad mem.json --now <current-ISO-time> [--skill signals-scout-general]
is what lets it score cadence adherence (the expected interval) and staleness (the
authoritative
, which the windowed runs can miss when the 100-row cap truncates the
newest runs). Without
the memory column shows
and no memory flags fire. The
emit % is the same summary-prose heuristic — cross-check signal-to-noise against
.
scripts/emitted_signals.py
— every finding the fleet actually emitted
Implements the "list what scouts have actually emitted" workflow: the authoritative per-finding
table (when, scout, severity, weight, confidence,
, one-line hypothesis) plus a
per-scout rollup (emit count, severity mix, weight range, latest emit). Unlike
's
emit
% — a prose heuristic — this reads the emitted signals directly, so it's exact.
Its input is
not a
tool; it's an
result over
(the general, any-team path). The full query lives in the script's header —
copy it verbatim.
returns a pipe-delimited text table (even under
it's
that text wrapped in a JSON string), so the script parses that text; the query deliberately selects
only pipe-safe scalar columns (the multi-line
is excluded,
is sanitized).
bash
# call --json execute-sql { "truncate": false, "query": "<emitted-signals query from the header>" } -> emitted.txt
python scripts/emitted_signals.py --signals emitted.txt --now <current-ISO-time> \
[--skill mcp-feedback,general] [--severity P0,P1,P2] [--since <ISO>] [--sort weight] [--wide]
takes a comma-separated set (the
prefix is optional).
adds the
so you can chain straight into
for the run that emitted a
finding. Remember the coverage caveat: this lists signals that
persisted — a finding a run
summary claims but that's absent here was gated (dry-run / AI processing not approved / source
disabled) or failed.
Tips
- Always surface the posture. "Running but in dry-run" is the single most common reason
a user thinks a scout is broken when it isn't.
- An empty close-out is success. Most runs should find nothing. Don't report a wall of clean,
empty runs as a problem.
- Emit-vs-quiet is a first-class run field. Filter runs directly with
(or read per run) to find what emitted, without parsing the prose . The
source_product: "signals_scout"
inbox filter lists the reports the fleet surfaced; an empty
result there means it hasn't emitted yet (scouts hold a high bar), not that the filter is broken.
- A ~30-min run that is usually a timeout, not a broken scout. Completed runs finish
in a couple of minutes. Most often the scout over-investigated and ran the full budget (the fleet
self-corrects by writing "tight-run recipe" scratchpad entries) — but some are false timeouts
where the scout actually finished in a few minutes and the run then hung on a dropped close-out.
The session log (above) tells them apart: real over-investigation shows tool calls right up to the
wall; a false timeout goes silent long before it. Don't assume over-investigation from duration
alone.
- Lead with the run , then offer for the full transcript — don't dump raw
run rows at the user.
- means a scout has never fired — check it's enabled and the project is
enrolled before digging further.
- To explain a quiet scout, read the project profile.
signals-scout-project-profile-get
shows whether the surface it watches is even in use — a logs scout on a project with no logs has
nothing to do.
- This skill is read-only. To change a scout's schedule, posture, or body, hand off to
the skill — it covers
signals-scout-config-update
and the
skills-store edit path.