Imported from nickmartin1ee7/LeafSweeper (AGENTS.md). Install upstream with npx skills add nickmartin1ee7/LeafSweeper. Copyright stays with the author.

AGENTS.md

Instructions for AI coding agents contributing to LeafSweeper — a Godot 4.7 (C# / .NET 8) Android puzzle game. This file is the operating manual: it holds everything an agent needs every session. For the rationale behind the workflow, the validation levels and a troubleshooting table, read docs/agentic-development.md once before the first dev task; when the two disagree, this file wins.

Validate after every change (in this order)

dotnet build                                   # 1. compile
godot --headless --import                      # 2. import assets/scenes
godot --headless --quit-after 180              # 3. boot smoke test
LEAF_AUTOPLAY=1 godot --headless --quit-after 4700   # 4. gameplay self-test

The binary on this machine is godot-mono (NixOS wrapper), not plain godot.
A fresh worktree needs --import before level 4, and autoplay silently exits 0 with no output without it — so does a --quit-after frame budget that runs out before the ~2.5s settle finishes (autoplay prints its first line only once the floor is dressed). Always grep for AUTOPLAY in the output; never trust the exit code alone; on missing lines rerun with a bigger budget — autoplay self-quits on pass or fail.
LEAF_AUTOPLAY resets the save and asserts a full round-trip; exit 0 on pass only after AUTOPLAY output is seen.
Visual slices: headless is blind. Temporarily add a LEAF_SHOT=<path> hook in Main._Ready, run windowed (headless has no framebuffer), inspect the PNG, then remove the hook before committing.

Cleanup after every Godot run (the tree dirties itself)

git checkout -- LeafSweeper.csproj; rm -f LeafSweeper.csproj.old
git diff --ignore-all-space --stat   # must be empty before committing; discard whitespace-only churn (repo standard is 4-space indent)

A new script's generated .cs.uid is committed together with the script.

Workflow

Start each dev task here; the why behind every step lives in docs/agentic-development.md.

Plan first, code second — planned work tracked as todos; one todo = one vertical slice. No drive-by refactors of unrelated code.
Implement each slice in a dedicated git worktree on a short-lived branch, never the main checkout (it carries human's in-progress edits):
```
git worktree add ../LeafSweeper-<slice> -b <slice>
# validate + atomic commits there, then push the branch and open a PR
# (push/PR only when the human asks — see rule 3):
git -c credential.helper= -c http.sslVerify=false push \
  "https://nickmartin1ee7:$(gh auth token)@github.com/<owner>/<repo>.git" <slice>
gh pr create --base main --head <slice>
# once the PR is merged on GitHub (pull/fetch may need the same token URL):
git pull; git worktree remove ../LeafSweeper-<slice>; git branch -d <slice>
```
Hard rule — PRs only: main advances exclusively through GitHub PRs. Never git merge a slice branch into main locally and never push directly to main. Hard rule for agent sessions: even when your session's working directory is the main checkout, do not edit repo files there — create the worktree before the first edit and work only inside it. If edits already landed in the main checkout, recover before continuing: dump the changed files to a patch in a persistent path (git diff -- <files> > ~/persistent/slice.patch), git worktree add a slice worktree, git apply the patch there, then git checkout -- <files> in the main checkout so it returns to its pre-session state. Verify with git status — only the human's own pre-existing edits may remain. Merged branches are never left behind.
Commit atomically — and only when the human asks: an agent session never commits, pushes or opens a PR on its own initiative; it hands off the slice green and uncommitted on its branch. When a commit is requested: one logical change per commit; message leads with the change, body explains the why; .uid/.import metadata in its own commit.
Docs live with code: behavior changes update README.md and docs/* in the same slice (numbers in prose drift fast).
Stop at "buildable and headlessly verified" and hand off to the human for playtesting; their findings become new todos. Feature changes gate on the human's playtest sign-off before code review (step 9 of the agentic workflow below), so feel problems never reach review; docs and chore slices may skip straight to review. Every handoff must end by asking the human whether to open a PR and merge it — don't make them ask.
The final steps of every slice are to create a PR and merge it: push the slice branch, open a PR against main (gh pr create --base main --head <slice>), and merge that PR on GitHub (gh pr merge or the GitHub UI) — never locally. A slice is only finished once its PR is merged and the worktree and branch are cleaned up; main never advances any other way (PR-only hard rule in step 2). Push, PR and merge happen only on the human's explicit yes to the rule-5 handoff question (rule 3).

Code practices

Scene tree is code-built: scenes/Main.tscn is a one-node shell; all nodes are constructed in Main.BuildTree(). Don't hand-edit .tscn state.
Difficulty tuning is pure functions of level number in scripts/RoundConfig.cs — playtest findings map to one named constant.
Feel tunables (sweep radius, friction, etc.) are named consts with comments explaining the feel they produce.
Reused nodes must clear old children before adding new ones: Setup() = teardown + build.
Z-order is an explicit ladder declared in Main.BuildTree, never tree-order luck; UI lives on a CanvasLayer, which ZIndex cannot beat.

Environment constraints

.NET target is pinned to net8.0 (local SDK is 8.0.x). Don't bump it alone.

git-remote-https is broken on this machine (CURL_OPENSSL_4 error). Push by injecting the gh token into the URL:

git -c credential.helper= -c http.sslVerify=false push \
  "https://nickmartin1ee7:$(gh auth token)@github.com/<owner>/<repo>.git" <branch>

/tmp is volatile between agent tool calls — keep scratch artifacts in persistent paths.
Keystores, Android SDK and JDK paths stay out of the repo (editor settings or keystore.env, which is gitignored).

Agentic workflow (mandatory, TODO-tracked)

CRITICAL: Every workflow step below MUST be tracked in the session SQL todos table. No step is considered complete until its TODO is marked done.

The following workflow complements the repository-specific guidance above. Each step corresponds to a session TODO that enforces progress tracking and audibility:
1. PRE-REQ: Track todos — Create a session TODO for every step below. Update todos as work progresses.
  - TODO id: agents-01-track-todos
  - This step is meta: you are doing it now by reading this file.
2. PRE-REQ: Work from worktree — Create a dedicated git worktree branch before editing.
  - TODO id: agents-02-use-worktree
  - Never edit the main checkout; commit only in the worktree.
3. ORIENT: Inventory & docs — List the project tree and read docs/ to identify touch points.
  - TODO id: agents-03-orient-inventory
  - Capture affected files and required doc updates.
4. ORIENT: Verify tooling — Ensure all required tools (dotnet, godot, gh, tests) work.
  - TODO id: agents-04-verify-tooling
  - Confirm versions and pinning; document any constraints.
5. DESIGN: Write a plan — Commit a short plan and test strategy.
  - TODO id: agents-05-plan
  - Include acceptance tests and rollback approach.
6. DESIGN: Research & verify — Search authoritative docs; cite and verify all claims.
  - TODO id: agents-06-research
  - No assumptions; all facts linked to online references.
7. DEVELOP: Atomic commits — Implement changes with small, focused commits; update docs inline.
  - TODO id: agents-07-develop-atomic
  - One logical change per commit; messages explain the why.
8. DEVELOP: Run tests — Execute and pass all tests that exercise the change.
  - TODO id: agents-08-test
  - Document test commands and outcomes in the PR.
9. PLAYTEST: Human playtest gate — For feature changes (anything that changes gameplay, visuals, or user-visible behavior), hand off to the human for playtesting after tests pass and before code review; findings become new todos and a failed playtest loops back to #7.
  - TODO id: agents-09-playtest-gate
  - Record the human's verdict (pass / findings) in the session todos; do not proceed to review without an explicit pass.
  - Docs and chore slices may skip this step with the human's okay.
10. REVIEW: Subagent review — Launch a high-reasoning review agent for independent inspection.
- TODO id: agents-10-review-subagent
- Docs-only slices (no code or runtime change) skip this gate on the human's standing instruction — mark the review todo done as waived instead of launching a reviewer.
- The reviewer must NEVER attempt to execute the Godot engine (no godot/godot-mono runs — no import, boot, or autoplay). Runtime and build validation is already done by the validating session; trust it.
- Review focus: code quality, maintainability, and reliability only — correctness of logic, readability, structure, edge cases, and error handling as visible in the diff and surrounding code.
  - Object-lifetime review (part of the gate): flag every diff line that can leak a Godot object or rendering resource — native objects handed back by calls like Texture2D.GetImage() without using/dispose, nodes removed with RemoveChild (or Reparent off a container) but never re-parented or freed, render targets (SubViewport size or GetTexture) allocated eagerly instead of on first use, and duplicate field reassignment that orphans the originally built node. See Godot object lifetime in docs/agentic-development.md.
- Reviewer reports PASS/FAIL with summary of critical findings.
1. GATE: Iterate on FAIL — If reviewer returns FAIL, loop back to #7, address issues, update TODOs.
  - TODO id: agents-11-gate-on-fail
  - Do not proceed until PASS (#GATE#).
2. GATE: Proceed on PASS — If reviewer returns PASS, prepare for merge.
  - TODO id: agents-12-gate-on-pass
  - Unblock merge actions (#GATE#).
3. CLEANUP: Create and merge PR — Open a GitHub PR from the worktree branch and merge via GitHub (not locally).
  - TODO id: agents-13-merge
  - PR title and description include test results, the human playtest verdict (feature slices) and the review summary.
  - REQUIRED: Merge via GitHub UI or gh CLI, never with git merge locally.
  - After GitHub merge, sync the worktree branch locally: git fetch origin main && git rebase origin/main.
4. CLEANUP: Delete worktree — Remove the local worktree and slice branch after remote merge is confirmed.
  - TODO id: agents-14-delete-worktree
  - Clean: git worktree remove <path> && git branch -d <slice>.
  - Verify on GitHub that the slice branch is deleted by GitHub's post-merge cleanup, or delete it manually: git push origin --delete <slice>.
5. IMPROVE: Update docs — Capture improvements back into AGENTS.md or docs/.
  - TODO id: agents-15-improve-docs
  - Share lessons with future agentic sessions.
Subtasks and discoveries

As work progresses, new TODOs may be discovered and added to the session todos table under the guided workflow. All subtasks must:
- Be linked to a parent workflow step (via todo_deps if dependencies exist).
- Use clear, actionable titles (gerund form: "Fixing authentication").
- Include enough detail that the task can be executed without external context.
NixOS git push guidance

When pushing from this machine, inject the gh auth token into the URL to avoid libcurl compatibility failures:
```
git -c credential.helper= -c http.sslVerify=false push \
  "https://nickmartin1ee7:$(gh auth token)@github.com/owner/repo.git" branch
```
Do not commit tokens; use gh CLI at push time.

LeafSweeper

About

AGENTS.md

Validate after every change (in this order)

Cleanup after every Godot run (the tree dirties itself)

Workflow

Code practices

Environment constraints

Agentic workflow (mandatory, TODO-tracked)

Subtasks and discoveries

NixOS git push guidance

Use it

Manifest

Reviews