Agent-Skills.md

Agent Skills: Claude Code Session Log Schema

Claude Code session log schema — JSONL record types, message structure, tool call/result pairing, subagent file locations, team session layout, task/plan/team configuration paths. Use when parsing ~/.claude/projects/**/*.jsonl files, writing PostToolUse hooks that measure response sizes, building session analyzers, or any agent that reads or queries Claude session transcripts.

UncategorizedID: Jamie-BitFlight/claude_skills/claude-session-data-schema-reference

Repository

Jamie-BitFlight/claude_skills
Jamie-BitFlightLicense: MIT
6110

Install this agent skill to your local

pnpm dlx add-skill https://github.com/Jamie-BitFlight/claude_skills/tree/HEAD/plugins/plugin-creator/skills/claude-session-data-schema-reference

Skill Files

Browse the full folder contents for claude-session-data-schema-reference.

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plugins/plugin-creator/skills/claude-session-data-schema-reference/SKILL.md

Skill Metadata

Name
claude-session-data-schema-reference
Description
Claude Code session log schema — JSONL record types, message structure, tool call/result pairing, subagent file locations, team session layout, task/plan/team configuration paths. Use when parsing ~/.claude/projects/**/*.jsonl files, writing PostToolUse hooks that measure response sizes, building session analyzers, or any agent that reads or queries Claude session transcripts.

Claude Code Session Log Schema

Reference skill for the JSONL session log format written by Claude Code under ~/.claude/projects/.

All claims in the reference are sourced from direct JSONL file inspection and verified against the LM Assist TypeScript source. No fields are inferred.

When to Load

Load ./references/schema.md when you need:

  • Directory structure and project-key encoding rules
  • Complete record type discriminator (system, user, assistant, result, progress, summary, file-history-snapshot)
  • Field-level schema for each record type
  • Tool call / tool result pairing algorithm
  • Subagent and team session file naming conventions
  • Task, plan, and team configuration paths
  • Hook integration — how PostToolUse tool_response maps to tool_result.content
  • What is NOT in the logs (per-tool token costs, streaming events, hook records, per-tool timing)

Source

Schema verified 2026-03-24. Source reference: ./references/schema.md.