<div align="center">

# screenshot-rename

*A Claude Code skill that turns a folder of timestamp-named screenshots*<br>
*into a folder of human-readable, searchable filenames —*<br>
*using parallel Haiku vision agents.*

[**Homepage**](https://pages.tojo.team/cardinale/screenshot-rename/) &nbsp;·&nbsp; [SKILL.md](SKILL.md) &nbsp;·&nbsp; [pipeline.py](pipeline.py) &nbsp;·&nbsp; [MIT](LICENSE)

<br>

<img src="assets/before-after.png" alt="Before / after — five real renames, including U+202F handling and user-keyword preservation" width="900">

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<br>

```
CleanShot 2026-04-15 at 09.14.07.png
   ↓
CleanShot - Shamel Studio Affiliate Referral Code Modal - 2026-04-15 at 09.14.07.png
```

Built for [CleanShot](https://cleanshot.com)-style screenshot folders, but works on any directory of `.png` / `.gif` / `.mp4` / `.pdf` files named only by timestamp. Recognizes both **`CleanShot ...`** and Apple **`Screenshot ...`** filenames in the same pass, preserves any leading user-typed keyword prefix, and is safe to re-run on a folder that's already partially renamed.

## Highlights

- **Parallel** — describes ~200 files in 3 minutes using 10 concurrent Haiku subagents.
- **Safe** — pre-builds the full rename plan in memory, validates uniqueness and target collisions, then renames atomically with a file-count audit. Designed after losing 4 files to a `mv` overwrite during prototyping.
- **Multi-prefix** — same pipeline handles `CleanShot ...`, Apple `Screenshot ...`, and files with hand-typed leading keywords (e.g. `jojo travel CleanShot ...`).
- **Idempotent** — re-running on a folder skips files already in the renamed `App - Description - timestamp.ext` form. No description-stacking.
- **Handles video / PDF** — extracts the first frame so vision agents can describe them.
- **Resizes for the vision tool** — Retina screenshots exceed Read's image cap; pipeline downsamples to 1568 px max.

## A session, end to end

<div align="center">

<img src="assets/session.png" alt="Claude Code session — user prompt, parallel Haiku fan-out across ten batches, receipt of the run" width="900">

</div>

The skill activates when you ask Claude conversationally. Behind the scenes it preps the folder, fans out ten Haiku agents in a single round-trip, validates the resulting plan, then applies the renames in a single Python pass with a file-count audit at the end.

## Installation

This is a Claude Code skill. Drop the repo into `~/.claude/skills/`:

```bash
git clone https://gitea.tojo.team/cardinale/screenshot-rename.git \
  ~/.claude/skills/screenshot-rename
```

In your next Claude Code session, ask:

> rename all the cleanshot files in `~/Documents/Screenshots/` based on their content

The skill will activate automatically from its description.

## Usage from the command line

You can also drive the pipeline directly:

```bash
# 1. Prep — extract frames, resize, build batches
python3 pipeline.py prep --src "/path/to/folder" --batch-size 19

# 2. (In a Claude Code session, dispatch one Haiku subagent per
#     /tmp/screenshot-rename/full-batch-NN file using the prompt template
#     in SKILL.md.)

# 3. Plan — aggregate descriptions, validate, build rename map
python3 pipeline.py plan --src "/path/to/folder"

# 4. Execute — apply the plan, audit file count
python3 pipeline.py execute --src "/path/to/folder"
```

The dispatch step (#2) currently requires a Claude Code session.

## What the parser accepts

| Form | Recognized | Becomes |
|---|---|---|
| `CleanShot 2026-MM-DD at HH.MM.SS.png` | yes | `CleanShot - <description> - 2026-MM-DD at HH.MM.SS.png` |
| `Screenshot 2026-MM-DD at H.MM.SS PM.png` (with U+202F) | yes — U+202F normalized to ASCII space | `Screenshot - <description> - 2026-MM-DD at H.MM.SS PM.png` |
| `<keywords> CleanShot 2026-MM-DD at HH.MM.SS.png` | yes — keywords title-cased and prepended to the AI description | `CleanShot - <Keywords + description> - 2026-MM-DD at HH.MM.SS.png` |
| `App - <description> - 2026-MM-DD at HH.MM.SS.png` | already renamed → **skipped** | (unchanged) |

## The gotchas this skill encodes

This skill exists because every one of these caused real damage during development:

1. The `Read` tool has an image-size cap. Resize first.
2. Vision can't read `.mp4` or multi-page `.pdf` directly. Extract a frame.
3. **Bash regex `[[ =~ ]]` does NOT populate `BASH_REMATCH` in zsh.** Targets become empty. Loops collide on the same filename. Files vanish. Use Python for any filename mutation.
4. `mv` silently overwrites. Use `mv -n` or `os.rename` with explicit pre-existence check.
5. Pre-build the entire rename plan in memory and validate uniqueness before any `mv`.
6. Audit `len(os.listdir(DEST))` before and after. Equal count == proof no overwrites.
7. iCloud-synced files in Time Machine local snapshots are file-provider stubs, not bytes. External backups (Backblaze, Time Machine to physical disk) are the real recovery source.
8. `Bash run_in_background` may exit early on `while read` loops. Run renames foreground via Python.
9. Haiku occasionally returns the resized `.jpg` filename instead of the original `.png`. Validator must try alt extensions.
10. Always preserve the original `.mp4` / `.pdf` extension — describe via the extracted frame, rename the source.
11. **macOS `Screenshot` filenames contain U+202F (NARROW NO-BREAK SPACE)** before AM/PM. Haiku echoes it as ASCII space, so a verbatim filename lookup misses every Screenshot file. Normalize on both sides of the lookup; emit ASCII space in the new name.
12. **Re-running is only safe if the parser skips already-renamed files.** Detect `^App - .+ - timestamp.ext$` and exclude.
13. **Leading user-typed keyword prefix is signal, not noise.** Title-case the keywords and prepend them to the AI description before assembling the new name.

The full discussion is in [SKILL.md](SKILL.md#the-critical-gotchas-every-one-of-these-caused-real-pain).

## Real-world impact

| Run | Files | What happened |
|---|---|---|
| 1 | 196 CleanShot | Lost 4 to the bash-regex-in-zsh gotcha (#3). |
| 2 | 196 CleanShot | Rebuilt with Python and `mv -n` — 189 renamed cleanly, zero loss. |
| 3 | 20 mixed (CleanShot + Apple Screenshot + one user-prefixed) | First plan attempt dropped every Screenshot file with a misleading `NO_DESC` error. Diagnosed the U+202F gotcha (#11) via `repr()` of the live filename. After adding U+202F normalization, multi-prefix support, and keyword preservation — all 20 renamed in one pass. |

## Roadmap

- Direct Anthropic API mode (no Claude Code session required) — needs `ANTHROPIC_API_KEY`
- Custom prompt templates per-folder
- Optional preservation of dots in technical strings (`v2.1` currently becomes `V21`)
- Dry-run flag on `execute`

## License

MIT — see [LICENSE](LICENSE).
