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exploring-llm-traces

ABSOLUTE MUST to debug and inspect LLM/AI agent traces using PostHog's MCP tools. Use when the user pastes a trace or session URL (e.g. /ai-observability/traces/<id> or /ai-observability/sessions/<id>), asks to debug a trace, figure out what went wrong, check if an agent used a tool correctly, verify context/files were surfaced, inspect subagent behavior, investigate LLM decisions, or analyze token usage and costs. Also use when raw SQL/HogQL against `events.properties.$ai_input` / `$ai_output_choices` returns empty — message content lives only on the dedicated `posthog.ai_events` table.

76

Quality

93%

Does it follow best practices?

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SecuritybySnyk

Low

Low-risk findings worth noting

SKILL.md
Quality
Evals
Security

Quality

Content

92%Weight 40%Scale 1-5

Reviews the quality of instructions and guidance provided to agents. Good implementation is clear, handles edge cases, and produces reliable results.

A highly actionable, well-structured skill body with executable examples, a clear sequenced debugging workflow, and clean progressive disclosure to verified reference files and scripts. The main improvement opportunity is deduplicating guidance repeated across the workflow, link-construction, and tips sections.

Suggestions

Consolidate the repeated '_posthogUrl always include' directive and date-range guidance so each appears once in its canonical section rather than re-stated in Step 2, 'Constructing UI links', and 'Tips'.

Merge the schema-discovery-first guidance, which is explained nearly identically in both the 'Finding traces' intro and the 'Discovering the schema first' subsection.

DimensionReasoningScore

Conciseness

Content is dense, domain-specific, and avoids explaining general concepts Claude already knows, but several points are repeated across sections (the '_posthogUrl always include' directive, date-range guidance, and schema-discovery-first rule each appear multiple times) and could be tightened.

4 / 5

Actionability

Provides fully executable, copy-paste-ready JSON tool-call payloads, bash script invocations with env vars, and concrete filter examples covering trace URLs, session URLs, model/person/external-ID filters, with only placeholder IDs to substitute.

5 / 5

Workflow Clarity

The URL-debug workflow is a clearly sequenced three-step process with explicit decision logic (trace vs session classification, date_from/date_to/timestamp handling) and a validation guardrail ('CRITICAL: Never assume event names... call read-data-schema first') before constructing filters.

5 / 5

Progressive Disclosure

SKILL.md acts as a well-signaled overview with one-level-deep markdown links to real bundle files (./references/events-and-properties.md, example-llm-trace.md.j2, example-llm-traces-list.md) and a scripts table linking to six existing ./scripts/*.py files, keeping bulk detail off the main page.

5 / 5

Total

19

/

20

Passed

Description

95%Weight 40%Scale 1-5

Based on the skill's description, can an agent find and select it at the right time? Clear, specific descriptions lead to better discovery.

A strong, highly trigger-rich description that clearly defines a narrow PostHog LLM-trace debugging niche with comprehensive natural language triggers. The only blemish is the 'ABSOLUTE MUST to' opening, which reads as buzzword over-claim rather than clean third-person declarative voice.

Suggestions

Replace the 'ABSOLUTE MUST to debug and inspect' opening with a clean third-person declarative such as 'Debugs and inspects LLM/AI agent traces using PostHog's MCP tools' to remove the over-claim buzzword.

DimensionReasoningScore

Specificity

Lists multiple concrete actions (debug, inspect, 'check if an agent used a tool correctly', 'verify context/files were surfaced', 'inspect subagent behavior', 'analyze token usage and costs'), but the opening 'ABSOLUTE MUST to' is an over-claim buzzword that slightly muddies an otherwise concrete action list.

4 / 5

Completeness

Explicitly answers both what ('debug and inspect LLM/AI agent traces using PostHog's MCP tools') and when (an extensive 'Use when...' clause with multiple concrete triggers and a SQL/HogQL fallback condition).

5 / 5

Trigger Term Quality

Comprehensive natural trigger phrases a user would actually say ('pastes a trace or session URL', 'asks to debug a trace', 'figure out what went wrong', 'analyze token usage and costs') plus concrete URL path examples and synonyms.

5 / 5

Distinctiveness Conflict Risk

Clear niche (PostHog AI observability trace/session debugging via MCP) with distinct triggers like specific UI URL paths and the HogQL-returns-empty condition, giving minimal conflict risk with other skills.

5 / 5

Total

19

/

20

Passed

Validation

100%

Checks the skill against the spec for correct structure and formatting. All validation checks must pass before discovery and implementation can be scored.

Validation16 / 16 Passed

Validation for skill structure

No warnings or errors.

Repository
PostHog/posthog
Reviewed

Table of Contents

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