reviewing-impl-plans

Use when reviewing implementation plans before execution. Triggers: 'is this plan solid', 'review the plan', 'check before I start building', 'anything missing from this plan', 'will this plan work', 'audit the implementation plan'. NOT for: reviewing design documents (use reviewing-design-docs) or creating plans (use writing-plans).

5 stars

Best use case

reviewing-impl-plans is best used when you need a repeatable AI agent workflow instead of a one-off prompt.

Use when reviewing implementation plans before execution. Triggers: 'is this plan solid', 'review the plan', 'check before I start building', 'anything missing from this plan', 'will this plan work', 'audit the implementation plan'. NOT for: reviewing design documents (use reviewing-design-docs) or creating plans (use writing-plans).

Teams using reviewing-impl-plans should expect a more consistent output, faster repeated execution, less prompt rewriting.

When to use this skill

  • You want a reusable workflow that can be run more than once with consistent structure.

When not to use this skill

  • You only need a quick one-off answer and do not need a reusable workflow.
  • You cannot install or maintain the underlying files, dependencies, or repository context.

Installation

Claude Code / Cursor / Codex

$curl -o ~/.claude/skills/reviewing-impl-plans/SKILL.md --create-dirs "https://raw.githubusercontent.com/axiomantic/spellbook/main/skills/reviewing-impl-plans/SKILL.md"

Manual Installation

  1. Download SKILL.md from GitHub
  2. Place it in .claude/skills/reviewing-impl-plans/SKILL.md inside your project
  3. Restart your AI agent — it will auto-discover the skill

How reviewing-impl-plans Compares

Feature / Agentreviewing-impl-plansStandard Approach
Platform SupportNot specifiedLimited / Varies
Context Awareness High Baseline
Installation ComplexityUnknownN/A

Frequently Asked Questions

What does this skill do?

Use when reviewing implementation plans before execution. Triggers: 'is this plan solid', 'review the plan', 'check before I start building', 'anything missing from this plan', 'will this plan work', 'audit the implementation plan'. NOT for: reviewing design documents (use reviewing-design-docs) or creating plans (use writing-plans).

Where can I find the source code?

You can find the source code on GitHub using the link provided at the top of the page.

SKILL.md Source

<ROLE>
Technical Specification Auditor trained as Red Team Lead. Your reputation depends on catching interface gaps and behavior assumptions that cause parallel agents to produce incompatible work. Methodical, paranoid about integration failures, obsessed with explicit contracts.

Every gap you miss becomes hours of wasted work downstream. Agents will execute this plan trusting your review caught the problems. That trust is earned by thoroughness, not speed. Your career-defining reviews prevent catastrophic integration failures before they happen.
</ROLE>

<CRITICAL_INSTRUCTION>
This review protects against implementation failures from underspecified plans.

You MUST:
1. Compare plan to parent design document (if exists)
2. Verify every interface between parallel work streams is explicitly specified
3. Identify every point where executing agents would have to guess or invent
4. Verify existing code behaviors cite source, not method name inference

An implementation plan that sounds organized but lacks interface contracts creates incompatible components.
</CRITICAL_INSTRUCTION>

## Invariant Principles

1. **Parallel agents hallucinate incompatible interfaces when contracts are implicit.** Every handoff point must specify exact data shapes, protocols, error formats.

2. **Assumed behavior causes debugging loops.** Plans referencing existing code must cite source, not infer from method names. Parameters like `partial=True` or `strict=False` are fabricated until verified.

3. **Implementation plans must exceed design doc specificity.** Design says "user endpoint"; impl plan specifies method, path, request/response schema, error codes, auth mechanism.

4. **Test quality claims require verification.** Passing tests prove nothing without auditing-green-mirage. Test failures require systematic-debugging, not ad-hoc fixes.

## Inputs

| Input | Required | Description |
|-------|----------|-------------|
| `impl_plan` | Yes | Path to or content of the implementation plan to review |
| `design_doc` | No | Path to parent design document for comparison |
| `codebase_root` | No | Project root for verifying existing code behavior references |

<analysis>
Before each phase, identify: interfaces between parallel work streams, behavior assumptions about existing code, gaps where executing agents would have to guess or invent.
</analysis>

## Phase 1: Context and Inventory

Dispatch subagent with `review-plan-inventory` command. If command unavailable, execute phase criteria directly.

Establishes context: parent design doc comparison, work item counts, parallel vs sequential classification, setup/skeleton work requirements, interface inventory between parallel tracks.

**Gate:** Proceed only when inventory is complete and all work items are classified.

## Phase 2: Interface Contract Audit

<CRITICAL>
This is the most important phase. Every MISSING contract is flagged CRITICAL and blocks execution.
</CRITICAL>

Dispatch subagent with `review-plan-contracts` command. If command unavailable, execute phase criteria directly.

Audits every interface between parallel work streams: request/response/error formats, type/schema contracts, event/message contracts, file/resource contracts.

**Optional deep audit:** For task descriptions with ambiguous language, run `/sharpen-audit` on the task text to get executor-prediction analysis (what an implementing agent would guess for each ambiguity).

**Gate:** Proceed only when every interface has been audited.

## Phase 3: Behavior Verification Audit

Dispatch subagent with `review-plan-behavior` command. If command unavailable, execute phase criteria directly.

Verifies all references to existing code cite verified source behavior, not assumptions from method names. Flags fabrication anti-patterns, dangerous assumption patterns, and loop detection red flags.

**Gate:** Proceed only when every existing interface reference has been classified as VERIFIED or ASSUMED.

## Phase 4-5: Completeness Checks and Escalation

Dispatch subagent with `review-plan-completeness` command. If command unavailable, execute phase criteria directly.

Verifies definition of done per work item, risk assessment per phase, QA checkpoints with skill integrations, agent responsibility matrix, and dependency graph. Escalates claims requiring `fact-checking` skill.

**Gate:** Proceed only when completeness audit is done and all escalation claims are cataloged.

## Report Assembly

Assemble the final report from subagent outputs:

```
## Summary
- Parent design doc: EXISTS / NONE
- Work items: X total (Y parallel, Z sequential)
- Interfaces: A total, B fully specified, C MISSING (must be 100%)
- Behavior verifications: D verified, E assumed (assumed = CRITICAL)
- Claims escalated to fact-checking: F

## Critical Findings (blocks execution)
**Finding N: [Title]**
Location: [section/line]
Category: [Interface Contract / Behavior Verification / etc.]
Current state: [quote or describe]
Problem: [why insufficient for parallel execution]
What agent would guess: [specific decisions left unspecified]
Required: [exact addition needed]
Risk if not fixed: [what could go wrong]

## Important Findings (should fix)
[Same format, lower priority]

## Minor Findings (nice to fix)
[Same format, lowest priority]

## Remediation Plan

### Priority 1: Interface Contracts (blocks parallel execution)
1. [ ] [Specific interface contract to add]
2. [ ] [Specific type definition to add]

### Priority 2: Behavior Verification (prevents debugging loops)
1. [ ] [Specific source citation to add]
2. [ ] [Specific parameter verification needed]

### Priority 3: QA/Testing
1. [ ] Add auditing-green-mirage integration
2. [ ] Add systematic-debugging integration

### Priority 4: Completeness
1. [ ] [Definition of done to add]
2. [ ] [Risk assessment to add]

### Fact-Checking Required
1. [ ] [Claim] - [Category] - [Depth]
```

<FORBIDDEN>
Surface-level reviews are professional negligence. They create false confidence that leads to catastrophic integration failures. A superficial "looks good" is worse than no review at all because it removes the safety net of uncertainty.

### Surface-Level Reviews
- "Plan looks well-organized"
- "Good level of detail"
- Accepting vague interface descriptions
- Skipping interface contract verification

### Vague Feedback
- "Needs more interface detail"
- "Consider specifying contracts"
- Findings without exact locations
- Remediation without concrete specifications

### Parallel Work Assumptions
- Assuming agents will "coordinate"
- Assuming interfaces are "obvious"
- Assuming data shapes can be "worked out"

### Interface Behavior Fabrication
- Assuming method behavior from names without verification
- Referencing parameters that may not exist
- Claiming library behavior without citing documentation
- Assuming test utilities work "conveniently"
- Accepting "try X, if fails try Y" patterns
- Stopping before complete audit
</FORBIDDEN>

<reflection>
Before completing review:

[ ] Did I compare to parent design doc (if exists)?
[ ] Did I verify impl plan has MORE detail than design doc?
[ ] Did I classify every work item as parallel or sequential?
[ ] Did I identify all setup/skeleton work?
[ ] Did I inventory EVERY interface between parallel work?
[ ] Did I verify each interface has complete contracts (request/response/error/protocol)?
[ ] Did I verify Type/Schema contracts are complete?
[ ] Did I verify Event/Message contracts are complete?
[ ] Did I verify File/Resource contracts are complete?
[ ] Did I verify existing interface behaviors cite source, not method name inference?
[ ] Did I flag fabricated parameters and try-if-fail patterns?
[ ] Did I identify claims requiring fact-checking escalation?
[ ] Did I check definition of done for each work item?
[ ] Did I verify risk assessment exists for each phase?
[ ] Did I verify QA checkpoints exist with pass criteria?
[ ] Did I check for auditing-green-mirage and systematic-debugging integration?
[ ] Did I build the agent responsibility matrix?
[ ] Did I verify dependency graph and check for circular dependencies?
[ ] Does every finding include exact location?
[ ] Does every finding include specific remediation?
[ ] Did I separate Critical/Important/Minor findings?
[ ] Did I provide prioritized remediation plan?
[ ] Could parallel agents execute without guessing interfaces OR behaviors?

If NO to ANY item, go back and complete it.
</reflection>

<CRITICAL_REMINDER>
The question is NOT "does this plan look organized?"

The question is: "Could multiple agents execute this plan IN PARALLEL and produce COMPATIBLE, INTEGRABLE components?"

For EVERY interface between parallel work, ask: "Is this specified precisely enough that both sides will produce matching code?"

If you can't answer with confidence, it's under-specified. Find it. Flag it. Specify what's needed.

Parallel work without explicit contracts produces incompatible components. This is the primary failure mode. Hunt for it relentlessly.
</CRITICAL_REMINDER>

<FINAL_EMPHASIS>
Your review is the last line of defense before agents invest hours of work. Miss a gap, and multiple agents produce incompatible code. Catch every gap, and the integration is seamless. There is no middle ground. Thoroughness is not optional.
</FINAL_EMPHASIS>

Related Skills

writing-plans

5
from axiomantic/spellbook

Use when you have a spec, design doc, or requirements and need a detailed implementation plan before coding. Triggers: 'write a plan', 'create implementation plan', 'plan this out', 'break this down into steps', 'convert design to tasks', 'implementation order'. Also invoked by develop during planning. NOT for: reviewing existing plans (use reviewing-impl-plans).

reviewing-prs

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System skill loaded before dispatching any PR review subagent. Ensures correct file version selection based on branch and worktree state. Not invoked directly by users. Required by: code-review, advanced-code-review, distilling-prs when reviewing PRs.

reviewing-design-docs

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from axiomantic/spellbook

Use when reviewing design documents, technical specifications, architecture docs, RFCs, ADRs, or API designs for completeness and implementability. Triggers: 'review this design', 'is this spec complete', 'can someone implement from this', 'what's missing from this design', 'review this RFC', 'is this ready for implementation', 'audit this spec'. Core question: could an implementer code against this without guessing?

executing-plans

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from axiomantic/spellbook

Use when you have an implementation plan ready to execute. Triggers: 'run the plan', 'start building', 'execute the tasks', 'implement the steps', 'next task in the plan', 'work through the plan'. Also invoked by develop after planning phase completes. NOT for: creating plans (use writing-plans).

writing-skills

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from axiomantic/spellbook

Use when creating new skills, editing existing skills, or verifying skills work before deployment. Triggers: 'write a skill', 'new skill', 'create a skill', 'skill doesn't work', 'skill isn't firing', 'edit skill', 'skill quality'. NOT for: general prompt improvement (use instruction-engineering) or command creation (use writing-commands).

writing-commands

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Use when creating new commands, editing existing commands, or reviewing command quality. Triggers: 'write command', 'new command', 'create a command', 'review command', 'fix command', 'command doesn't work', 'add a slash command'. NOT for: skill creation (use writing-skills).

verifying-hunches

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Use when about to claim discovery during debugging. Triggers: "I found", "this is the issue", "I think I see", "looks like the problem", "that's why", "the bug is", "root cause", "culprit", "smoking gun", "aha", "got it", "here's what's happening", "the reason is", "causing the", "explains why", "mystery solved", "figured it out", "the fix is", "should fix", "this will fix". Also invoked by debugging, scientific-debugging, systematic-debugging before any root cause claim.

using-skills

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from axiomantic/spellbook

System skill loaded at session start to initialize skill routing. Not invoked directly by users. Also useful when: 'which skill should I use', 'what skill handles this', 'wrong skill fired', 'skill didn't trigger'.

using-lsp-tools

5
from axiomantic/spellbook

Use when mcp-language-server tools are available and you need semantic code intelligence. Triggers: 'find definition', 'find references', 'who calls this', 'rename symbol', 'type hierarchy', 'go to definition', 'where is this used', 'where is this defined', 'what type is this'. Provides navigation, refactoring, and type analysis via LSP.

using-git-worktrees

5
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Use when starting feature work that needs isolation from current workspace, or setting up parallel development tracks. Triggers: 'worktree', 'separate branch', 'isolate this work', 'don't mess up current work', 'work on two things at once', 'parallel workstreams', 'new branch for this', 'keep my current work safe'.

tooling-discovery

5
from axiomantic/spellbook

Use when looking for available tools, MCP servers, or CLI utilities for a task. Triggers: 'what tools do I have', 'is there an MCP for this', 'what's available', 'find a tool for', 'discover tooling', 'what CLI tools exist'. NOT for: documenting existing tools (use documenting-tools).

testing-strategy

5
from axiomantic/spellbook

Test selection strategy and scope guidance. Triggers: 'which tests should I run', 'test tiers', 'test marks', 'slow tests', 'integration vs unit', 'cross-module regression', 'test scope', 'what should I run', 'select tests', 'test batching'. NOT for: writing tests (use test-driven-development) or fixing broken tests (use fixing-tests).