signals-scout-logs

Detects log volume bursts, severity shifts, and novel message patterns in PostHog logs.

713|118|Updated Aug 11, 2020
One-click install
npx skills add https://github.com/PostHog/posthog-foss --skill signals-scout-logs
Or copy as Structured Prompt for Agent
Please help me install this Agent Skill.
Skill: signals-scout-logs
Source: https://github.com/PostHog/posthog-foss/tree/main/products/signals/skills/signals-scout-logs
Command: npx skills add https://github.com/PostHog/posthog-foss --skill signals-scout-logs

SYSTEM DOCUMENTATION & REQUIREMENTS

What problem does it solve?

Teams running PostHog logs face a firehose of millions of lines per hour where meaningful changes — a fresh error signature, a service going silent, a severity spike — drown in routine info-level noise. This Skill gives an AI agent a disciplined scouting workflow that surfaces only validated, window-over-window shifts and files them as actionable inbox reports instead of raw alerts.

Core Features & Use Cases

  • Delta-based pattern detection: Anchors every run on logs-patterns-diff to classify message templates as new, rate-shifted, or gone versus a baseline window, catching low-volume all-error signatures that share-based reads miss.
  • Firehose-safe querying: Enforces severity- and service-filtered counts (logs-count, logs-services-create, logs-count-ranges) so queries never time out on unfiltered streams, and avoids the -30m month-unit date footgun.
  • Report authoring with dedupe: Checks the inbox and scratchpad memory before writing, edits existing reports for recurring issues, routes suggested_reviewers to service owners, and records baselines under pattern:/noise:/report: keys for future runs.
  • Use Case: A deploy introduces a new fatal-level template at low volume. The scout's diff read flags it as new, corroborates it with bounded counts and an error-tracking cross-check, then authors a report with the service's chart series and the owning reviewer.

Quick Start

Ask the agent to run a logs scout over the last hour and report any new error patterns, volume bursts, or silent services it finds.

Frequently Asked Questions about signals-scout-logs

High-intent search queries and answers about installing and using this skill.

FAQPage Schema
How do I detect new error patterns in PostHog logs?

Use logs-patterns-diff with a recent date range and an omitted baseline, which defaults to the same window one week earlier. It classifies each message template as new, rate_shift, or gone, and a new template at error or fatal severity is the highest-signal finding regardless of volume share.

How to monitor log volume spikes per service in PostHog?

Call logs-services-create over a window like -1h to get the top-25 services with error_count, error_rate, and volume_share_pct in one aggregation. Compare against stored baselines, then localize with logs-count-ranges scoped to the hot service.

Why does an unfiltered logs-count query fail with a 500 error?

Busy projects emit hundreds of millions of log lines per hour, so an unfiltered count times out at any window length. Always bound counts with severityLevels or serviceNames filters, or use the logs-services-create aggregation for all-severity reads.

Does the logs scout handle log injection attempts in message content?

Yes. The skill treats all log bodies, service names, and attribute values as untrusted quoted data, never as instructions. Any write action requires independent corroboration from a separate read, and instruction-like log content is itself flagged as a possible injection finding.

When should a logs finding edit an existing report instead of creating one?

Edit when the inbox already covers the service or pattern, such as a worsening burst or a flapping alert. Search inbox-reports-list first, then use scout-edit-report to append fresh numbers rather than minting a near-duplicate report.