jsonl-log-analyzer

jsonl-log-analyzer is a skill for Claude Code from zircote-plugins/claude-team-orchestration. It costs 58 tokens per session (3,261 once invoked), scanned A, original, MIT.

A method for analyzing large JSONL log files, where each line is a separate JSON record. It discovers the data fields, divides the file into chunks, analyzes those chunks, and combines the results.

In plain words
What is it for?
Use it to inspect log schemas, create jq extraction steps, investigate incidents, find patterns across records, and produce a combined analysis of large JSONL files.
Why use it?
It makes large logs manageable when the entire file cannot fit into one working context and adapts the analysis to the log's actual structure.

Skill for Claude Code

Written for Claude Code: user-invocable in frontmatter.

Part of the swarm plugin — 10 skills, 5 agents shipped together

Good fit Use it to inspect log schemas, create jq extraction steps, investigate incidents, find patterns across records, and produce a combined analysis of large JSONL files.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/zircote-plugins/claude-team-orchestration/jsonl-log-analyzer
Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

Any agent
npx skills add zircote-plugins/claude-team-orchestration --skill jsonl-log-analyzer
Clone the repo
git clone --depth 1 https://github.com/zircote-plugins/claude-team-orchestration

Made for: Claude Code.

Or install swarm, the plugin that ships this one along with the rest of its 10 skills, 5 agents.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for jsonl-log-analyzer

README.md
[![agentmods](https://agentmods.dev/badge/skills/zircote-plugins/claude-team-orchestration/jsonl-log-analyzer/github.svg)](https://agentmods.dev/skills/zircote-plugins/claude-team-orchestration/jsonl-log-analyzer)
Your own site
<a href="https://agentmods.dev/skills/zircote-plugins/claude-team-orchestration/jsonl-log-analyzer"><img src="https://agentmods.dev/badge/skills/zircote-plugins/claude-team-orchestration/jsonl-log-analyzer/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for jsonl-log-analyzer

Your own site · 80×15
<a href="https://agentmods.dev/skills/zircote-plugins/claude-team-orchestration/jsonl-log-analyzer"><img src="https://agentmods.dev/badge/skills/zircote-plugins/claude-team-orchestration/jsonl-log-analyzer.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 58 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 3,261 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5.1 $0.00058 $0.03261
Opus 5 $0.00029 $0.01631
Sonnet 5 $0.00012 $0.00652
Haiku 4.5 $0.00006 $0.00326

Measured 9d ago against content hash 2260009c95b1, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-09, from the pricing page.

Security

Grade A, and why

jsonl-log-analyzer scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 9d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

skills/jsonl-log-analyzer/SKILL.md · 301 lines

How it starts

The opening of the file, as written. The whole thing — 301 lines — stays where its author put it; the contents beside it link to each section on GitHub.

JSONL Log Analyzer

Automated schema-aware analysis of large JSONL log files. Discovers the field schema dynamically, generates tailored jq extraction recipes, and orchestrates the standard RLM fan-out/fan-in pipeline — making JSONL log analysis a single-prompt operation.

Related skills:


Architecture

flowchart TD
    A[User prompt + JSONL file path] --> B[Phase 1: Schema Discovery]
    B -->|inline: head + jq| C[Schema extract + field classification]
    C --> D[Phase 2: Partition & Generate Prompts]
    D -->|chunk file by line count| E[Chunk 1]
    D --> F[Chunk 2]
    D --> G[Chunk N]
    E --> H["swarm:rlm-json-analyzer<br/>(Haiku)"]
    F --> I["swarm:rlm-json-analyzer<br/>(Haiku)"]
    G --> J["swarm:rlm-json-analyzer<br/>(Haiku)"]
    H --> K[Phase 3: Synthesis]
    I --> K
    J --> K
    K -->|"swarm:rlm-synthesizer<br/>(Sonnet)"| L[Final Report]

Three phases:

  1. Schema Discovery — Extract field paths, types, and presence counts using head/tail + jq. No raw log lines enter the orchestrator's context.
  2. Partition & Generate Prompts — Split the file by line count, generate per-chunk analyst prompts with schema summary and tailored jq recipes.
  3. Synthesis — Aggregate analyst findings into a coherent report with log-specific guidance (temporal patterns, error clustering, service breakdown).

When to Use

Scenario Use This Skill?
Large JSONL log file (>1500 lines) Yes
Incident investigation in structured logs Yes
Traffic/request analysis from JSONL event streams Yes
JSONL files with unknown or evolving schema Yes
Plain text logs (unstructured) No — use basic RLM with swarm:rlm-chunk-analyzer
Small JSONL file (<1500 lines) No — Claude handles it directly
JSON array (not line-delimited) No — use Content-Aware JSON RLM
CSV/TSV data files No — use Content-Aware CSV RLM

Read the full file on GitHub · 301 lines

Files

What ships with it

2 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 9d ago First seen · 301 lines · 58 tokens per session scan A 2260009c95b1

Subscribe to this mod's changes

jsonl-log-analyzer is a skill published in the GitHub repository zircote-plugins/claude-team-orchestration (14 stars, last pushed 2d ago), licensed MIT. It adds 58 tokens to every session and 3,261 once invoked, about $0.0003 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.