And Or Planner

AND/OR Planner

Announce at start: "Using and-or-planner to structure this task before execution."

What This Does

Before executing a complex task, this skill generates an AND/OR tree that makes the task's structure explicit: AND nodes enforce that all required subtasks complete; OR nodes pre-rank alternative approaches and try them in order on failure. The tree is written to .and-or-plan.md and updated live during execution.

This addresses two failure modes:

• Premature abandonment — giving up when the first approach fails instead of trying alternatives
• Incomplete completion — stopping when some required subtasks succeed instead of all of them

Step 1: Trigger Check

Run this self-assessment before generating the tree:

1. Conjunctive check — does this task require multiple distinct things that ALL must succeed?
2. Alternative check — does this task have multiple valid approaches where one might fail?
3. Complexity floor — does the task involve 3+ discrete steps OR any external dependency (package, service, API)?

Fire if: (Check 1 OR Check 2) AND Check 3.

If the trigger condition is not met, stop here — execute the task normally without a tree.

Step 2: Generate the Tree

Analyze the task and produce an AND/OR tree. Apply these rules before writing:

Generation rules:

1. Root is always an AND node (the overall goal requires all subtasks)
2. OR nodes represent points where multiple approaches exist — score each child 0.0–1.0 by estimated likelihood of success in this codebase context. Highest score = tried first.
3. OR nodes must have ≥2 children. If you produce a single-child OR, collapse it — replace the OR node with its child directly.
4. AND nodes represent groups where all children must complete.
5. ACTION nodes are atomic leaf operations: a single command, file write, or verifiable step.
6. Every node must have a type and status. Every OR child must have a score.

On generation failure (malformed tree, file write error): warn — ⚠ AND/OR tree generation failed: [reason]. Falling back to linear execution. — and proceed without a tree.

Step 3: Write .and-or-plan.md

Check if .and-or-plan.md already exists:

• Status: in_progress → context reset; skip to Step 5 (Resume)
• Status: completed or Status: failed → archive it first: move to .claude/and-or-history/YYYY-MM-DD-[slug].md (create dir if needed), then overwrite

Write the file at the project root:

# AND/OR Plan: [task description]
Generated: [ISO 8601 timestamp]
Status: in_progress

## Tree

- AND: [root goal] [PENDING]
  - OR: [sub-goal] [PENDING]
    - ACTION: [approach 1] (score: 0.9) [PENDING]
    - ACTION: [approach 2] (score: 0.6) [PENDING]
  - AND: [required group] [PENDING]
    - ACTION: [step 1] [PENDING]
    - ACTION: [step 2] [PENDING]

Node statuses: PENDING → IN_PROGRESS → SUCCESS | FAILED | PRUNED

PRUNED is applied to OR siblings that are never attempted because an earlier sibling succeeded. Do not leave them as PENDING — mark them PRUNED when the OR node resolves to SUCCESS.

Update node statuses in this file throughout execution. The file reflects live state — it's resumable and user-editable.

If a .gitignore exists, suggest adding:

.and-or-plan.md
.claude/and-or-history/

Step 4: Execute the Tree (DFS)

Traverse depth-first. Update node status to IN_PROGRESS when entering, then SUCCESS or FAILED on completion.

AND nodes

Execute all children sequentially. Mark SUCCESS when all children are SUCCESS. If any child reaches FAILED, mark the AND node FAILED immediately — do not continue remaining children. Propagate failure up to the parent.

OR nodes

Execute children in descending score order. Mark SUCCESS as soon as any child succeeds — do not execute remaining children.

On child failure:

1. Announce (non-blocking, no confirmation needed):

`` ⟳ Approach failed: [child name] — [brief reason] Trying next: [next child name] (score: [score]) ``

1. Rollback side effects from the failed child (uninstall packages, revert created files)

• If rollback fails: mark the OR node FAILED, surface to user:

⚠ Rollback failed for [approach]: [reason]. Cannot safely attempt next branch. Stop — do not attempt remaining OR children from a dirty state.

1. Attempt next child

On child success: mark all remaining unexecuted OR siblings PRUNED, then mark the OR node SUCCESS. Do not leave untried siblings as PENDING.

If all OR children fail: mark OR node FAILED, propagate up.

ACTION nodes

Execute the atomic operation. Verify the outcome. Mark SUCCESS or FAILED.

Step 5: File Lifecycle

On success (root AND reaches SUCCESS)

1. Update file: Status: completed
2. Move .and-or-plan.md → .claude/and-or-history/YYYY-MM-DD-[task-slug].md

(create .claude/and-or-history/ if it doesn't exist)

On failure (all branches exhausted, root FAILED)

1. Update file: Status: failed
2. Leave .and-or-plan.md in place
3. Surface summary to user:

``` ✗ AND/OR plan failed.

Tried:

• [branch 1]: [failure reason]
• [branch 2]: [failure reason]

Blocked on: [specific node and reason] To resume after editing: change Status: failed to Status: in_progress in .and-or-plan.md — Claude will detect it on next context start. ```

On context reset (Step 5, Resume)

.and-or-plan.md exists with Status: in_progress at session start:

1. Announce: Found in-progress AND/OR plan — resuming from [node name]
2. Traverse from the last IN_PROGRESS node, or the first PENDING node if no IN_PROGRESS nodes exist
3. Within AND nodes: skip children already in SUCCESS state — do not re-run succeeded work
4. Continue DFS normally from the resume point

Reference Example

Task: "Set up authentication — install JWT library, create middleware, add tests"

Trigger check:

• Check 1: Yes — install + middleware + tests must ALL succeed
• Check 2: Yes — jsonwebtoken or jose are both valid
• Check 3: Yes — 3+ steps, external package dependency
• Result: FIRE

Generated tree:

# AND/OR Plan: Set up authentication
Generated: 2026-03-11T15:00:00Z
Status: in_progress

## Tree

- AND: Set up authentication [IN_PROGRESS]
  - OR: JWT library [PENDING]
    - ACTION: npm install jsonwebtoken (score: 0.9) [PENDING]
    - ACTION: npm install jose (score: 0.6) [PENDING]
  - AND: Middleware [PENDING]
    - ACTION: Create src/middleware/auth.ts [PENDING]
    - ACTION: Register middleware in src/app.ts [PENDING]
  - AND: Tests [PENDING]
    - ACTION: Write unit tests for token generation [PENDING]
    - ACTION: Write integration tests for protected routes [PENDING]

Execution trace:

1. Enter root AND → IN_PROGRESS
2. Enter OR (JWT library) → IN_PROGRESS
3. Attempt npm install jsonwebtoken → fails (peer dep conflict)
4. Announce: ⟳ Approach failed: npm install jsonwebtoken — peer dependency conflict with Node 22. Trying next: npm install jose (score: 0.6)
5. Rollback: npm uninstall jsonwebtoken → succeeds
6. Attempt npm install jose → SUCCESS
7. OR node → SUCCESS
8. Enter AND (Middleware) → execute Create auth.ts → SUCCESS → Register middleware → SUCCESS → AND SUCCESS
9. Enter AND (Tests) → execute unit tests → SUCCESS → integration tests → SUCCESS → AND SUCCESS
10. Root AND → SUCCESS
11. Update Status: completed, move file to .claude/and-or-history/

Note: this trace exercises the failure-then-success OR path (first child fails, second succeeds) — both children are attempted, so no PRUNED siblings are produced in this trace. The PRUNED-on-first-success scenario (first child succeeds, remaining siblings marked PRUNED) is covered by the "Correct PRUNED status" scenario in ~/.claude/skills/and-or-planner/VERIFICATION-SCENARIOS.md, which is the authoritative reference for that behavior.

For all failure-path traces (OR exhaustion, rollback failure, multi-level AND propagation), also treat VERIFICATION-SCENARIOS.md as the authoritative reference.

Source & license

This open-source skill is cataloged on AgentStack and links to its original source — we do not rehost the code.

• Author: tonysina
• Source: tonysina/claude-skills
• License: MIT

Install and usage instructions live in the source repository linked above.