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lightrun-slow-execution-diagnosis

Diagnose performance incidents in running services with Lightrun MCP: slow endpoints, latency or SLO regressions, timeouts, deadline-exceeded errors, hangs, and slowness that is intermittent, sporadic, occasional, happens only sometimes, or appears only under load. Use when diagnosing a performance incident; prefer this over lightrun-live-runtime-debugging, including for mixed slow-and-incorrect cases. Use slow-execution snapshots when a duration boundary separates problematic executions; use focused active-path snapshots or call stacks for known hangs that may not reach an end marker. Select the narrowest code section, derive an evidence-based threshold, and correlate captured state with code and telemetry. Use lightrun-live-runtime-debugging for non-performance diagnosis and lightrun-ask-prod for one-off timing, when available; otherwise report the scope gap. Do not use for pull-request review, code changes, setup, deployment, or post-deployment performance validation.

1.95x
Quality

97%

Does it follow best practices?

Impact

96%

1.95x

1 of 3 eval scenarios. Add 2 more for a full score.

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 tightly written operational runbook: concrete executable tool-call examples with exact polling timing, explicit validation checkpoints and fallback paths, and clean one-level-deep progressive disclosure. The only weakness is minor redundancy between the Activation gate/Preflight checkpoint and the bullets they restate.

Suggestions

Fold the Activation gate's 'Apply the description's scope exactly' into the Preflight intro and drop the Checkpoint line that repeats the preflight bullets, reclaiming a few lines without losing any gate.

Consider trimming the long required-contents lists per outcome ('blocked', 'reproduction-required', etc.) to the fields that vary per outcome, since several items (question, target, threshold provenance) are already mandated in the common 'Always include' list.

DimensionReasoningScore

Conciseness

The body is dense and directive with no concept explanations Claude already knows and a compact runtime-support table, but has minor trimmable redundancy: the Activation gate re-states the description's scope ('Apply the description's scope exactly') and the Preflight checkpoint repeats conditions already given as bullets. Fits 'efficient; minor instances that could be trimmed' rather than 'every token earns its place'.

4 / 5

Actionability

Fully executable guidance: a copy-paste-ready execution_duration_create quickstart with concrete parameters (startLine 120, snapshotThresholdMs 450, snapshotExpressions), the exact two-branch polling sequence, and a specific backoff schedule ('poll after 2 seconds; then wait 1, 2, and 5 seconds... about 15 seconds'). Threshold derivation is properly delegated to the referenced workflow file.

5 / 5

Workflow Clarity

Clear sequence (Preflight -> explicit Checkpoint -> evidence-path selection with fallbacks -> target selection -> runtime gate -> capture/poll -> one terminal outcome) with explicit validation steps and error-recovery feedback: 'Do not create an action after source-discovery failure or a confirmed code-version mismatch', 'Revalidate targeting or capability failures before repeating', and per-outcome retry conditions for blocked/inconclusive.

5 / 5

Progressive Disclosure

Two well-signaled, one-level-deep references (both verified to exist with no nested links), each introduced with its purpose ('to enumerate tools, select sources...'; 'for threshold derivation, marker placement, create parameters, dual-lifecycle polling, and resume state'), with bulk detail correctly split out and a concrete quickstart kept inline.

5 / 5

Total

19

/

20

Passed

Description

100%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.

The description is specific, comprehensive, and trigger-rich, with explicit what/when guidance and unusually strong routing rules against sibling skills including the mixed slow-and-incorrect edge case. Third-person voice is used consistently and no clause is padded fluff.

DimensionReasoningScore

Specificity

Lists multiple concrete actions (diagnose slow endpoints, latency/SLO regressions, timeouts, deadline-exceeded errors, hangs; select the narrowest code section; derive an evidence-based threshold; correlate captured state with code and telemetry) with comprehensive domain coverage and consistent third-person voice, matching the 'comprehensive coverage' anchor with no coverage gaps.

5 / 5

Completeness

Explicitly answers both what ('Diagnose performance incidents in running services with Lightrun MCP: slow endpoints, latency or SLO regressions, timeouts...') and when ('Use when diagnosing a performance incident' plus a negative scope 'Do not use for pull-request review, code changes, setup, deployment...') with concrete trigger phrases.

5 / 5

Trigger Term Quality

Natural incident vocabulary with deliberate synonym coverage: 'slow endpoints', 'latency or SLO regressions', 'timeouts', 'deadline-exceeded errors', 'hangs', 'intermittent, sporadic, occasional, happens only sometimes, or appears only under load' — the exact phrases a user would say during a performance incident.

5 / 5

Distinctiveness Conflict Risk

Clear performance-diagnosis niche with explicit routing against sibling skills ('prefer this over lightrun-live-runtime-debugging, including for mixed slow-and-incorrect cases'; 'Use lightrun-live-runtime-debugging for non-performance diagnosis and lightrun-ask-prod for one-off timing'), actively minimizing conflict risk beyond just distinct triggers.

5 / 5

Total

20

/

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.

Validation — 16 / 16 Passed

Validation for skill structure

No warnings or errors.

Repository

lightrun-platform/lightrun-ai

Path

skills/lightrun-slow-execution-diagnosis/SKILL.md

Reviewed

Table of Contents

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