claude-code-types

TypeScript type definitions for Claude Code chat history JSONL files.

Claude Code stores conversation history at ~/.claude/projects/<project-slug>/<session-id>.jsonl. Each line is a JSON object. This package provides full type coverage for all entry types.

Install

npm install claude-code-types

Usage

import type { TranscriptEntry } from 'claude-code-types';
import { readFileSync } from 'fs';

const path = '~/.claude/projects/my-project/abc123.jsonl';
const entries: TranscriptEntry[] = readFileSync(path, 'utf-8')
  .split('\n')
  .filter(Boolean)
  .map(line => JSON.parse(line) as TranscriptEntry);

for (const entry of entries) {
  switch (entry.type) {
    case 'user':
      console.log(entry.message.content);
      break;
    case 'assistant':
      console.log(entry.message.model);
      break;
    case 'system':
      console.log(entry.subtype);
      break;
  }
}

Entry types

| type | Interface | Description | |--------|-----------|-------------| | user | UserEntry | Human messages, tool results | | assistant | AssistantEntry | Model responses, tool calls | | system | SystemEntry | API errors, compaction, durations | | file-history-snapshot | FileHistorySnapshotEntry | Undo/restore tracking | | pr-link | PrLinkEntry | Linked pull requests | | progress | ProgressEntry | Streaming subagent updates | | queue-operation | QueueOperationEntry | Queued user messages | | saved_hook_context | SavedHookContextEntry | Hook execution context | | summary | SummaryEntry | Conversation summaries |

Versioning

This project follows Semantic Versioning 2.0.0. See CHANGELOG.md for release history.

Contributing

See AGENTS.md for publishing instructions and project conventions.

License

MIT

"Claude" is a trademark of Anthropic, PBC. This project is not affiliated with, endorsed by, or sponsored by Anthropic.