Agent Skills' simplify-ignore hook stops deleting the code you hid from Claude

2 hours ago

Agent Skills 0.6.13 (October 13, 2026) fixes two bugs in the simplify-ignore hook for Claude Code: one could delete the code you had hidden from /code-simplify, the other brought back a change you had reverted with git. Also: test-driven-development now fires when you paste code and ask for tests or a fix, and /review and /test are documented as running in your main session. Release notes: https://github.com/addyosmani/agent-skills/releases/tag/0.6.13 Lost block fix: https://github.com/addyosmani/agent-skills/pull/649 Revert fix: https://github.com/addyosmani/agent-skills/pull/651 test-driven-development: https://github.com/addyosmani/agent-skills/pull/678 /review and /test: https://github.com/addyosmani/agent-skills/pull/682

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  1. 0:00Agent Skills' simplify-ignore hook stops deleting the code you hid from Claude
  2. 0:18Deleting a placeholder line used to erase the protected block
  3. 0:35If the placeholder is still missing at Stop, your edits wait in a .recovered file
  4. 0:50A git revert during simplification now stays reverted
  5. 1:08test-driven-development now starts when you paste a function and ask for tests or a fix
  6. 1:31/review and /test run their skill in your main session, without a subagent
  7. 1:46Also in 0.6.13, two more code samples that failed as written
Show transcript

Agent Skills' simplify-ignore hook stops deleting the code you hid from Claude

github.com/addyosmani/agent-skills · release 0.6.13Oct 13, 2026
// what /code-simplify shows Claude
/* BLOCK_de115a1d: perf-critical */
result[0] = buf[0] ^ key[0]; lost
hooks/simplify-ignore.sh · PRs #649 and #651 · release 0.6.13

Addy Osmani's Agent Skills, version 0.6.13, fixes two bugs in its simplify-ignore hook for Claude Code. The hook hides code you mark from the code simplify skill. One bug could delete that hidden code, and the other brought back a change you had reverted.

Deleting a placeholder line used to erase the protected block

PR #649 · merged Oct 10, 2026release 0.6.13
function eq(a, b) {
/* BLOCK_de115a1d: constant-time compare */
return d === 0;
0.6.12
lost in 6 of 6
gone from the file, the backup and the cache
0.6.13
kept in 6 of 6
the edit goes back to Claude with the placeholder to restore
PR #649 · hooks/SIMPLIFY-IGNORE.md

Claude sees each hidden block as a one-line placeholder. If an edit deleted that line, say while clearing dead comments, the hook saved the file without the block, and the code was gone for good. Now the hook rejects that edit and tells Claude which placeholder to put back.

If the placeholder is still missing at Stop, your edits wait in a .recovered file

hooks/SIMPLIFY-IGNORE.mdrelease 0.6.13
file on disk ← original, from the backup
.claude/.simplify-ignore-cache/<id>.recovered
← the session's changes, merged back by hand
hooks/SIMPLIFY-IGNORE.md, Known limitations · PR #649

There is a limit. If the placeholder is still missing when the session stops, the hook restores the original file. Claude's changes are kept as a recovered copy in the hook's cache, and you merge them back by hand.

A git revert during simplification now stays reverted

PR #651 · merged Oct 13, 2026release 0.6.13
after git checkout, restore, stash or reset0.6.120.6.13
The reverted change at Stopback 6/6gone 6/6
Hidden code on the next readshownhidden
PR #651 · hooks/simplify-ignore.sh

The code simplify skill tells the agent to revert any simplification that fails the tests, and agents revert with git. The hook then restored its old backup, bringing back the rejected change, and showed Claude the hidden code. Now the revert stays, and the code stays hidden.

test-driven-development now starts when you paste a function and ask for tests or a fix

PR #678 · merged Oct 13, 2026Claude Opus 5.5 · Claude Code
code pasted inline, skill firedbeforeafter
“Add unit tests for this function.”0 of 66 of 6
“Fix this bug: splitCents(100, 3) …”0 of 66 of 6
“Change this function so that …”0 of 61 of 6
PR #678 · skills/test-driven-development/SKILL.md · 0 false fires in 24 nearby prompts

The test driven development skill now fires when you paste a function and ask for tests, or paste a bug without mentioning tests. On Claude Opus 5.5 in Claude Code, both went from never firing to firing every time. Asking to change a function's behavior still fires in only one run of six.

/review and /test run their skill in your main session, without a subagent

PR #682 · merged Oct 13, 2026release 0.6.13
/review/testcode-reviewertest-engineer
CriticalRequiredOptionalNit

In Claude Code, use /agent-skills:review where a built-in command has the same name.

PR #682 · issue #681 · README

The /review and /test commands run their skill in your main session. The docs said they started the code reviewer and test engineer personas, and now they say what the commands do. Review findings now use the same four severity labels as the skill.

Also in 0.6.13, two more code samples that failed as written

github.com/addyosmani/agent-skills · release 0.6.13Oct 13, 2026
frontend-ui-engineering · the error state called a refetch that was never defined
hardening reference · the zod title check accepted a title made only of spaces
Release notes · github.com/addyosmani/agent-skills/releases/tag/0.6.13
release 0.6.13 · PRs #638 and #639

Two more code samples are fixed. The frontend skill's error state called a refetch function that was never defined, and a zod title check accepted a title made only of spaces. The rest of the changes are in the 0.6.13 release notes.