backfill

A command that rebuilds time-tracking records from existing Claude Code session transcripts. It reads session event logs, identifies projects and ticket IDs, and writes timelog entries.

In plain words
What is it for?
Backfilling past sessions, regenerating logs after configuration changes, and reporting the number, date range, and location of created entries.
Why use it?
It fills in historical time data when tracking was set up late or its detection rules changed. It can be run repeatedly without duplicating entries.

Command

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.

agentmods
npx agentmods add commands/remotecto/claude-code-timelog/backfill
Clone the repo
git clone --depth 1 https://github.com/RemoteCTO/claude-code-timelog
Per session 23 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 294 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
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 $0.00023 $0.00294
Opus 5 $0.00012 $0.00147
Sonnet 5 $0.00005 $0.00059
Haiku 4.5 $0.00002 $0.00029

Measured 2d ago against content hash 07adc9d5e67e, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

backfill 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 2d 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.

commands/backfill.md · 39 lines

What it actually says

Timelog Backfill

Process all existing Claude Code session transcripts and generate timelog entries for historical sessions.

Your task

  1. Run the backfill script:

    node ${CLAUDE_PLUGIN_ROOT}/scripts/backfill.mjs
    
  2. The script:

    • Scans ~/.claude/sessions/ for all JSONL transcripts
    • Extracts SessionStart, UserPromptSubmit, SessionEnd events
    • Detects project names and ticket IDs
    • Writes entries to ~/.claude/timelog/ (or $CLAUDE_TIMELOG_DIR)
    • Outputs progress every 100 files
  3. Report the summary to the user (number of entries, date range, output location).

When to use this

  • First-time setup: backfill all historical sessions
  • After fixing ticket detection patterns: re-run to update logs
  • After changing CLAUDE_TIMELOG_DIR: regenerate logs in new location

Notes

  • Safe to run multiple times (appends, doesn't duplicate)
  • Filters out system-injected messages (not real user prompts)
  • Uses the same config as live hooks (~/.claude/timelog/config.json)
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. 2d ago First seen · 39 lines · 23 tokens per session scan A 07adc9d5e67e

Subscribe to this mod's changes

backfill is a command published in the GitHub repository RemoteCTO/claude-code-timelog (7 stars, last pushed 6mo ago), licensed Apache-2.0. It adds 23 tokens to every session and 294 once invoked, about $0.0001 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 2026-08-31.