---
name: ce-plan
description: "Create structured plans for any multi-step task -- software features, research workflows, events, study plans, or any goal that benefits from structured breakdown. Also deepen existing plans with interactive review of sub-agent findings. Use for plan creation when the user says 'plan this', 'create a plan', 'write a tech plan', 'plan the implementation', 'how should we build', 'what's the approach for', 'break this down', 'plan a trip', 'create a study plan', or when a brainstorm/requirements document is ready for planning. Use for plan deepening when the user says 'deepen the plan', 'deepen my plan', 'deepening pass', or uses 'deepen' in reference to a plan. For exploratory or ambiguous requests where the user is unsure what to do, prefer ce-brainstorm first."
argument-hint: "[optional: feature description, requirements doc path, plan path to deepen, or any task to plan]"
---

# Create Technical Plan

**Note: The current year is 2026.** Use this when dating plans and searching for recent documentation.

`ce-brainstorm` defines **WHAT** to build. `ce-plan` defines **HOW** to build it. `ce-work` executes the plan. A prior brainstorm is useful context but never required — `ce-plan` works from any input: a requirements doc, a bug report, a feature idea, or a rough description.

**When directly invoked, always plan.** Never classify a direct invocation as "not a planning task" and abandon the workflow. If the input is unclear, ask clarifying questions or use the planning bootstrap (Phase 0.4) to establish enough context — but always stay in the planning workflow.

This workflow produces a durable implementation plan. It does **not** implement code, run tests, or learn from execution-time results. If the answer depends on changing code and seeing what happens, that belongs in `ce-work`, not here.

## Interaction Method

Use the platform's question tool when available. When asking the user a question, prefer the platform's blocking question tool if one exists (`AskUserQuestion` in Claude Code, `request_user_input` in Codex, `ask_user` in Gemini). Otherwise, present numbered options in chat and wait for the user's reply before proceeding.

Ask one question at a time. Prefer a concise single-select choice when natural options exist.

## Feature Description

<feature_description> #$ARGUMENTS </feature_description>

**If the feature description above is empty, ask the user:** "What would you like to plan? Describe the task, goal, or project you have in mind." Then wait for their response before continuing.

If the input is present but unclear or underspecified, do not abandon — ask one or two clarifying questions, or proceed to Phase 0.4's planning bootstrap to establish enough context. The goal is always to help the user plan, never to exit the workflow.

**IMPORTANT: All file references in the plan document must use repo-relative paths (e.g., `src/models/user.rb`), never absolute paths (e.g., `/Users/name/Code/project/src/models/user.rb`). This applies everywhere — implementation unit file lists, pattern references, origin document links, and prose mentions. Absolute paths break portability across machines, worktrees, and teammates.**

## Core Principles

1. **Use requirements as the source of truth** - If `ce-brainstorm` produced a requirements document, planning should build from it rather than re-inventing behavior.
2. **Decisions, not code** - Capture approach, boundaries, files, dependencies, risks, and test scenarios. Do not pre-write implementation code or shell command choreography. Pseudo-code sketches or DSL grammars that communicate high-level technical design are welcome when they help a reviewer validate direction — but they must be explicitly framed as directional guidance, not implementation specification.
3. **Research before structuring** - Explore the codebase, institutional learnings, and external guidance when warranted before finalizing the plan.
4. **Right-size the artifact** - Small work gets a compact plan. Large work gets more structure. The philosophy stays the same at every depth.
5. **Separate planning from execution discovery** - Resolve planning-time questions here. Explicitly defer execution-time unknowns to implementation.
6. **Keep the plan portable** - The plan should work as a living document, review artifact, or issue body without embedding tool-specific executor instructions.
7. **Carry execution posture lightly when it matters** - If the request, origin document, or repo context clearly implies test-first, characterization-first, or another non-default execution posture, reflect that in the plan as a lightweight signal. Do not turn the plan into step-by-step execution choreography.
8. **Honor user-named resources** - When the user names a specific resource — a CLI, MCP server, URL, file, doc link, or prior artifact — treat it as authoritative input, not a suggestion. Discover it if unknown (`command -v`, fetch, read) before assuming it's unavailable. Use it in place of generic alternatives. If it fails or doesn't exist, say so explicitly rather than silently substituting.

## Plan Quality Bar

Every plan should contain:
- A clear problem frame and scope boundary
- Concrete requirements traceability back to the request or origin document
- Repo-relative file paths for the work being proposed (never absolute paths — see Planning Rules)
- Explicit test file paths for feature-bearing implementation units
- Decisions with rationale, not just tasks
- Existing patterns or code references to follow
- Enumerated test scenarios for each feature-bearing unit, specific enough that an implementer knows exactly what to test without inventing coverage themselves
- Clear dependencies and sequencing

A plan is ready when an implementer can start confidently without needing the plan to write the code for them.

## Workflow

### Phase 0: Resume, Source, and Scope

#### 0.1 Resume Existing Plan Work When Appropriate

If the user references an existing plan file or there is an obvious recent matching plan in `docs/plans/`:
- Read it
- Confirm whether to update it in place or create a new plan
- If updating, preserve completed checkboxes and revise only the still-relevant sections

**Deepen intent:** The word "deepen" (or "deepening") in reference to a plan is the primary trigger for the deepening fast path. When the user says "deepen the plan", "deepen my plan", "run a deepening pass", or similar, the target document is a **plan** in `docs/plans/`, not a requirements document. Use any path, keyword, or context the user provides to identify the right plan. If a path is provided, verify it is actually a plan document. If the match is not obvious, confirm with the user before proceeding.

Words like "strengthen", "confidence", "gaps", and "rigor" are NOT sufficient on their own to trigger deepening. These words appear in normal editing requests ("strengthen that section about the diagram", "there are gaps in the test scenarios") and should not cause a holistic deepening pass. Only treat them as deepening intent when the request clearly targets the plan as a whole and does not name a specific section or content area to change — and even then, prefer to confirm with the user before entering the deepening flow.

Once the plan is identified and appears complete (all major sections present, implementation units defined, `status: active`):
- If the plan lacks YAML frontmatter (non-software plans use a simple `# Title` heading with `Created:` date instead of frontmatter), route to `references/universal-planning.md` for editing or deepening instead of Phase 5.3. Non-software plans do not use the software confidence check.
- Otherwise, short-circuit to Phase 5.3 (Confidence Check and Deepening) in **interactive mode**. This avoids re-running the full planning workflow and gives the user control over which findings are integrated.

Normal editing requests (e.g., "update the test scenarios", "add a new implementation unit", "strengthen the risk section") should NOT trigger the fast path — they follow the standard resume flow.

If the plan already has a `deepened: YYYY-MM-DD` frontmatter field and there is no explicit user request to re-deepen, the fast path still applies the same confidence-gap evaluation — it does not force deepening.

#### 0.1b Classify Task Domain

If the task involves building, modifying, or architecting software (references code, repos, APIs, databases, or asks to build/modify/deploy), continue to Phase 0.2.

If the domain is genuinely ambiguous (e.g., "plan a migration" with no other context), ask the user before routing.

Otherwise, read `references/universal-planning.md` and follow that workflow instead. Skip all subsequent phases. Named tools or source links don't change this routing — they're inputs, handled per Core Principle 8.

#### 0.2 Find Upstream Requirements Document

Before asking planning questions, search `docs/brainstorms/` for files matching `*-requirements.md`.

**Relevance criteria:** A requirements document is relevant if:
- The topic semantically matches the feature description
- It was created within the last 30 days (use judgment to override if the document is clearly still relevant or clearly stale)
- It appears to cover the same user problem or scope

If multiple source documents match, ask which one to use using the platform's blocking question tool when available (see Interaction Method). Otherwise, present numbered options in chat and wait for the user's reply before proceeding.

#### 0.3 Use the Source Document as Primary Input

If a relevant requirements document exists:
1. Read it thoroughly
2. Announce that it will serve as the origin document for planning
3. Carry forward all of the following:
   - Problem frame
   - Requirements and success criteria
   - Scope boundaries
   - Key decisions and rationale
   - Dependencies or assumptions
   - Outstanding questions, preserving whether they are blocking or deferred
4. Use the source document as the primary input to planning and research
5. Reference important carried-forward decisions in the plan with `(see origin: <source-path>)`
6. Do not silently omit source content — if the origin document discussed it, the plan must address it even if briefly. Before finalizing, scan each section of the origin document to verify nothing was dropped.

If no relevant requirements document exists, planning may proceed from the user's request directly.

#### 0.4 Planning Bootstrap (No Requirements Doc or Unclear Input)

If no relevant requirements document exists, or the input needs more structure:
- Assess whether the request is already clear enough for direct technical planning — if so, continue to Phase 0.5
- If the ambiguity is mainly product framing, user behavior, or scope definition, recommend `ce-brainstorm` as a suggestion — but always offer to continue planning here as well
- If the user wants to continue here (or was already explicit about wanting a plan), run the planning bootstrap below

The planning bootstrap should establish:
- Problem frame
- Intended behavior
- Scope boundaries and obvious non-goals
- Success criteria
- Blocking questions or assumptions

Keep this bootstrap brief. It exists to preserve direct-entry convenience, not to replace a full brainstorm.

If the bootstrap uncovers major unresolved product questions:
- Recommend `ce-brainstorm` again
- If the user still wants to continue, require explicit assumptions before proceeding

If the bootstrap reveals that a different workflow would serve the user better:

- **Symptom without a root cause** (user describes broken behavior but hasn't identified why) — announce that investigation is needed before planning and load the `ce-debug` skill. A plan requires a known problem to solve; debugging identifies what that problem is. Announce the routing clearly: "This needs investigation before planning — switching to ce-debug to find the root cause."
- **Clear task ready to execute** (known root cause, obvious fix, no architectural decisions) — suggest `ce-work` as a faster alternative alongside continuing with planning. The user decides.

#### 0.5 Classify Outstanding Questions Before Planning

If the origin document contains `Resolve Before Planning` or similar blocking questions:
- Review each one before proceeding
- Reclassify it into planning-owned work **only if** it is actually a technical, architectural, or research question
- Keep it as a blocker if it would change product behavior, scope, or success criteria

If true product blockers remain:
- Surface them clearly
- Ask the user, using the platform's blocking question tool when available (see Interaction Method), whether to:
  1. Resume `ce-brainstorm` to resolve them
  2. Convert them into explicit assumptions or decisions and continue
- Do not continue planning while true blockers remain unresolved

#### 0.6 Assess Plan Depth

Classify the work into one of these plan depths:

- **Lightweight** - small, well-bounded, low ambiguity
- **Standard** - normal feature or bounded refactor with some technical decisions to document
- **Deep** - cross-cutting, strategic, high-risk, or highly ambiguous implementation work

If depth is unclear, ask one targeted question and then continue.

### Phase 1: Gather Context

#### 1.1 Local Research (Always Runs)

Prepare a concise planning context summary (a paragraph or two) to pass as input to the research agents:
- If an origin document exists, summarize the problem frame, requirements, and key decisions from that document
- Otherwise use the feature description directly

Run these agents in parallel:

- Task research:ce-repo-research-analyst(Scope: technology, architecture, patterns. {planning context summary})
- Task research:ce-learnings-researcher(planning context summary)
Collect:
- Technology stack and versions (used in section 1.2 to make sharper external research decisions)
- Architectural patterns and conventions to follow
- Implementation patterns, relevant files, modules, and tests
- AGENTS.md guidance that materially affects the plan, with CLAUDE.md used only as compatibility fallback when present
- Institutional learnings from `docs/solutions/`

**Slack context** (opt-in) — never auto-dispatch. Route by condition:

- **Tools available + user asked**: Dispatch `research:ce-slack-researcher` with the planning context summary in parallel with other Phase 1.1 agents. If the origin document has a Slack context section, pass it verbatim so the researcher focuses on gaps. Include findings in consolidation.
- **Tools available + user didn't ask**: Note in output: "Slack tools detected. Ask me to search Slack for organizational context at any point, or include it in your next prompt."
- **No tools + user asked**: Note in output: "Slack context was requested but no Slack tools are available. Install and authenticate the Slack plugin to enable organizational context search."

#### 1.1b Detect Execution Posture Signals

Decide whether the plan should carry a lightweight execution posture signal.

Look for signals such as:
- The user explicitly asks for TDD, test-first, or characterization-first work
- The origin document calls for test-first implementation or exploratory hardening of legacy code
- Local research shows the target area is legacy, weakly tested, or historically fragile, suggesting characterization coverage before changing behavior

When the signal is clear, carry it forward silently in the relevant implementation units.

Ask the user only if the posture would materially change sequencing or risk and cannot be responsibly inferred.

#### 1.2 Decide on External Research

Based on the origin document, user signals, and local findings, decide whether external research adds value.

**Read between the lines.** Pay attention to signals from the conversation so far:
- **User familiarity** — Are they pointing to specific files or patterns? They likely know the codebase well.
- **User intent** — Do they want speed or thoroughness? Exploration or execution?
- **Topic risk** — Security, payments, external APIs warrant more caution regardless of user signals.
- **Uncertainty level** — Is the approach clear or still open-ended?

**Leverage ce-repo-research-analyst's technology context:**

The ce-repo-research-analyst output includes a structured Technology & Infrastructure summary. Use it to make sharper external research decisions:

- If specific frameworks and versions were detected (e.g., Rails 7.2, Next.js 14, Go 1.22), pass those exact identifiers to ce-framework-docs-researcher so it fetches version-specific documentation
- If the feature touches a technology layer the scan found well-established in the repo (e.g., existing Sidekiq jobs when planning a new background job), lean toward skipping external research -- local patterns are likely sufficient
- If the feature touches a technology layer the scan found absent or thin (e.g., no existing proto files when planning a new gRPC service), lean toward external research -- there are no local patterns to follow
- If the scan detected deployment infrastructure (Docker, K8s, serverless), note it in the planning context passed to downstream agents so they can account for deployment constraints
- If the scan detected a monorepo and scoped to a specific service, pass that service's tech context to downstream research agents -- not the aggregate of all services. If the scan surfaced the workspace map without scoping, use the feature description to identify the relevant service before proceeding with research

**Always lean toward external research when:**
- The topic is high-risk: security, payments, privacy, external APIs, migrations, compliance
- The codebase lacks relevant local patterns -- fewer than 3 direct examples of the pattern this plan needs
- Local patterns exist for an adjacent domain but not the exact one -- e.g., the codebase has HTTP clients but not webhook receivers, or has background jobs but not event-driven pub/sub. Adjacent patterns suggest the team is comfortable with the technology layer but may not know domain-specific pitfalls. When this signal is present, frame the external research query around the domain gap specifically, not the general technology
- The user is exploring unfamiliar territory
- The technology scan found the relevant layer absent or thin in the codebase

**Skip external research when:**
- The codebase already shows a strong local pattern -- multiple direct examples (not adjacent-domain), recently touched, following current conventions
- The user already knows the intended shape
- Additional external context would add little practical value
- The technology scan found the relevant layer well-established with existing examples to follow

Announce the decision briefly before continuing. Examples:
- "Your codebase has solid patterns for this. Proceeding without external research."
- "This involves payment processing, so I'll research current best practices first."

#### 1.3 External Research (Conditional)

If Step 1.2 indicates external research is useful, run these agents in parallel:

- Task research:ce-best-practices-researcher(planning context summary)
- Task research:ce-framework-docs-researcher(planning context summary)

#### 1.4 Consolidate Research

Summarize:
- Relevant codebase patterns and file paths
- Relevant institutional learnings
- Organizational context from Slack conversations, if gathered (prior discussions, decisions, or domain knowledge relevant to the feature)
- External references and best practices, if gathered
- Related issues, PRs, or prior art
- Any constraints that should materially shape the plan

#### 1.4b Reclassify Depth When Research Reveals External Contract Surfaces

If the current classification is **Lightweight** and Phase 1 research found that the work touches any of these external contract surfaces, reclassify to **Standard**:

- Environment variables consumed by external systems, CI, or other repositories
- Exported public APIs, CLI flags, or command-line interface contracts
- CI/CD configuration files (`.github/workflows/`, `Dockerfile`, deployment scripts)
- Shared types or interfaces imported by downstream consumers
- Documentation referenced by external URLs or linked from other systems

This ensures flow analysis (Phase 1.5) runs and the confidence check (Phase 5.3) applies critical-section bonuses. Announce the reclassification briefly: "Reclassifying to Standard — this change touches [environment variables / exported APIs / CI config] with external consumers."

#### 1.5 Flow and Edge-Case Analysis (Conditional)

For **Standard** or **Deep** plans, or when user flow completeness is still unclear, run:

- Task workflow:ce-spec-flow-analyzer(planning context summary, research findings)

Use the output to:
- Identify missing edge cases, state transitions, or handoff gaps
- Tighten requirements trace or verification strategy
- Add only the flow details that materially improve the plan

### Phase 2: Resolve Planning Questions

Build a planning question list from:
- Deferred questions in the origin document
- Gaps discovered in repo or external research
- Technical decisions required to produce a useful plan

For each question, decide whether it should be:
- **Resolved during planning** - the answer is knowable from repo context, documentation, or user choice
- **Deferred to implementation** - the answer depends on code changes, runtime behavior, or execution-time discovery

Ask the user only when the answer materially affects architecture, scope, sequencing, or risk and cannot be responsibly inferred. Use the platform's blocking question tool when available (see Interaction Method).

**Do not** run tests, build the app, or probe runtime behavior in this phase. The goal is a strong plan, not partial execution.

### Phase 3: Structure the Plan

#### 3.1 Title and File Naming

- Draft a clear, searchable title using conventional format such as `feat: Add user authentication` or `fix: Prevent checkout double-submit`
- Determine the plan type: `feat`, `fix`, or `refactor`
- Build the filename following the repository convention: `docs/plans/YYYY-MM-DD-NNN-<type>-<descriptive-name>-plan.md`
  - Create `docs/plans/` if it does not exist
  - Check existing files for today's date to determine the next sequence number (zero-padded to 3 digits, starting at 001)
  - Keep the descriptive name concise (3-5 words) and kebab-cased
  - Examples: `2026-01-15-001-feat-user-authentication-flow-plan.md`, `2026-02-03-002-fix-checkout-race-condition-plan.md`
  - Avoid: missing sequence numbers, vague names like "new-feature", invalid characters (colons, spaces)

#### 3.2 Stakeholder and Impact Awareness

For **Standard** or **Deep** plans, briefly consider who is affected by this change — end users, developers, operations, other teams — and how that should shape the plan. For cross-cutting work, note affected parties in the System-Wide Impact section.

#### 3.3 Break Work into Implementation Units

Break the work into logical implementation units. Each unit should represent one meaningful change that an implementer could typically land as an atomic commit.

Good units are:
- Focused on one component, behavior, or integration seam
- Usually touching a small cluster of related files
- Ordered by dependency
- Concrete enough for execution without pre-writing code
- Marked with checkbox syntax for progress tracking

Avoid:
- 2-5 minute micro-steps
- Units that span multiple unrelated concerns
- Units that are so vague an implementer still has to invent the plan

#### 3.4 High-Level Technical Design (Optional)

Before detailing implementation units, decide whether an overview would help a reviewer validate the intended approach. This section communicates the *shape* of the solution — how pieces fit together — without dictating implementation.

**When to include it:**

| Work involves... | Best overview form |
|---|---|
| DSL or API surface design | Pseudo-code grammar or contract sketch |
| Multi-component integration | Mermaid sequence or component diagram |
| Data pipeline or transformation | Data flow sketch |
| State-heavy lifecycle | State diagram |
| Complex branching logic | Flowchart |
| Mode/flag combinations or multi-input behavior | Decision matrix (inputs -> outcomes) |
| Single-component with non-obvious shape | Pseudo-code sketch |

**When to skip it:**
- Well-patterned work where prose and file paths tell the whole story
- Straightforward CRUD or convention-following changes
- Lightweight plans where the approach is obvious

Choose the medium that fits the work. Do not default to pseudo-code when a diagram communicates better, and vice versa.

Frame every sketch with: *"This illustrates the intended approach and is directional guidance for review, not implementation specification. The implementing agent should treat it as context, not code to reproduce."*

Keep sketches concise — enough to validate direction, not enough to copy-paste into production.

#### 3.4b Output Structure (Optional)

For greenfield plans that create a new directory structure (new plugin, service, package, or module), include an `## Output Structure` section with a file tree showing the expected layout. This gives reviewers the overall shape before diving into per-unit details.

**When to include it:**
- The plan creates 3+ new files in a new directory hierarchy
- The directory layout itself is a meaningful design decision

**When to skip it:**
- The plan only modifies existing files
- The plan creates 1-2 files in an existing directory — the per-unit file lists are sufficient

The tree is a scope declaration showing the expected output shape. It is not a constraint — the implementer may adjust the structure if implementation reveals a better layout. The per-unit `**Files:**` sections remain authoritative for what each unit creates or modifies.

#### 3.5 Define Each Implementation Unit

For each unit, include:
- **Goal** - what this unit accomplishes
- **Requirements** - which requirements or success criteria it advances
- **Dependencies** - what must exist first
- **Files** - repo-relative file paths to create, modify, or test (never absolute paths)
- **Approach** - key decisions, data flow, component boundaries, or integration notes
- **Execution note** - optional, only when the unit benefits from a non-default execution posture such as test-first or characterization-first
- **Technical design** - optional pseudo-code or diagram when the unit's approach is non-obvious and prose alone would leave it ambiguous. Frame explicitly as directional guidance, not implementation specification
- **Patterns to follow** - existing code or conventions to mirror
- **Test scenarios** - enumerate the specific test cases the implementer should write, right-sized to the unit's complexity and risk. Consider each category below and include scenarios from every category that applies to this unit. A simple config change may need one scenario; a payment flow may need a dozen. The quality signal is specificity — each scenario should name the input, action, and expected outcome so the implementer doesn't have to invent coverage. For units with no behavioral change (pure config, scaffolding, styling), use `Test expectation: none -- [reason]` instead of leaving the field blank.
  - **Happy path behaviors** - core functionality with expected inputs and outputs
  - **Edge cases** (when the unit has meaningful boundaries) - boundary values, empty inputs, nil/null states, concurrent access
  - **Error and failure paths** (when the unit has failure modes) - invalid input, downstream service failures, timeout behavior, permission denials
  - **Integration scenarios** (when the unit crosses layers) - behaviors that mocks alone will not prove, e.g., "creating X triggers callback Y which persists Z". Include these for any unit touching callbacks, middleware, or multi-layer interactions
- **Verification** - how an implementer should know the unit is complete, expressed as outcomes rather than shell command scripts

Every feature-bearing unit should include the test file path in `**Files:**`.

Use `Execution note` sparingly. Good uses include:
- `Execution note: Start with a failing integration test for the request/response contract.`
- `Execution note: Add characterization coverage before modifying this legacy parser.`
- `Execution note: Implement new domain behavior test-first.`

Do not expand units into literal `RED/GREEN/REFACTOR` substeps.

#### 3.6 Keep Planning-Time and Implementation-Time Unknowns Separate

If something is important but not knowable yet, record it explicitly under deferred implementation notes rather than pretending to resolve it in the plan.

Examples:
- Exact method or helper names
- Final SQL or query details after touching real code
- Runtime behavior that depends on seeing actual test failures
- Refactors that may become unnecessary once implementation starts

### Phase 4: Write the Plan

Use one planning philosophy across all depths. Change the amount of detail, not the boundary between planning and execution.

#### 4.1 Plan Depth Guidance

**Lightweight**
- Keep the plan compact
- Usually 2-4 implementation units
- Omit optional sections that add little value

**Standard**
- Use the full core template, omitting optional sections (including High-Level Technical Design) that add no value for this particular work
- Usually 3-6 implementation units
- Include risks, deferred questions, and system-wide impact when relevant

**Deep**
- Use the full core template plus optional analysis sections where warranted
- Usually 4-8 implementation units
- Group units into phases when that improves clarity
- Include alternatives considered, documentation impacts, and deeper risk treatment when warranted

#### 4.1b Optional Deep Plan Extensions

For sufficiently large, risky, or cross-cutting work, add the sections that genuinely help:
- **Alternative Approaches Considered**
- **Success Metrics**
- **Dependencies / Prerequisites**
- **Risk Analysis & Mitigation**
- **Phased Delivery**
- **Documentation Plan**
- **Operational / Rollout Notes**
- **Future Considerations** only when they materially affect current design

Do not add these as boilerplate. Include them only when they improve execution quality or stakeholder alignment.

#### 4.2 Core Plan Template

Omit clearly inapplicable optional sections, especially for Lightweight plans.

```markdown
---
title: [Plan Title]
type: [feat|fix|refactor]
status: active
date: YYYY-MM-DD
origin: docs/brainstorms/YYYY-MM-DD-<topic>-requirements.md  # include when planning from a requirements doc
deepened: YYYY-MM-DD  # optional, set when the confidence check substantively strengthens the plan
---

# [Plan Title]

## Overview

[What is changing and why]

## Problem Frame

[Summarize the user/business problem and context. Reference the origin doc when present.]

## Requirements Trace

- R1. [Requirement or success criterion this plan must satisfy]
- R2. [Requirement or success criterion this plan must satisfy]

## Scope Boundaries

- [Explicit non-goal or exclusion]

<!-- Optional: When some items are planned work that will happen in a separate PR, issue,
     or repo, use this sub-heading to distinguish them from true non-goals. -->
### Deferred to Separate Tasks

- [Work that will be done separately]: [Where or when -- e.g., "separate PR in repo-x", "future iteration"]

## Context & Research

### Relevant Code and Patterns

- [Existing file, class, component, or pattern to follow]

### Institutional Learnings

- [Relevant `docs/solutions/` insight]

### External References

- [Relevant external docs or best-practice source, if used]

## Key Technical Decisions

- [Decision]: [Rationale]

## Open Questions

### Resolved During Planning

- [Question]: [Resolution]

### Deferred to Implementation

- [Question or unknown]: [Why it is intentionally deferred]

<!-- Optional: Include when the plan creates a new directory structure (greenfield plugin,
     new service, new package). Shows the expected output shape at a glance. Omit for plans
     that only modify existing files. This is a scope declaration, not a constraint --
     the implementer may adjust the structure if implementation reveals a better layout. -->
## Output Structure

    [directory tree showing new directories and files]

<!-- Optional: Include this section only when the work involves DSL design, multi-component
     integration, complex data flow, state-heavy lifecycle, or other cases where prose alone
     would leave the approach shape ambiguous. Omit it entirely for well-patterned or
     straightforward work. -->
## High-Level Technical Design

> *This illustrates the intended approach and is directional guidance for review, not implementation specification. The implementing agent should treat it as context, not code to reproduce.*

[Pseudo-code grammar, mermaid diagram, data flow sketch, or state diagram — choose the medium that best communicates the solution shape for this work.]

## Implementation Units

- [ ] **Unit 1: [Name]**

**Goal:** [What this unit accomplishes]

**Requirements:** [R1, R2]

**Dependencies:** [None / Unit 1 / external prerequisite]

**Files:**
- Create: `path/to/new_file`
- Modify: `path/to/existing_file`
- Test: `path/to/test_file`

**Approach:**
- [Key design or sequencing decision]

**Execution note:** [Optional test-first, characterization-first, or other execution posture signal]

**Technical design:** *(optional -- pseudo-code or diagram when the unit's approach is non-obvious. Directional guidance, not implementation specification.)*

**Patterns to follow:**
- [Existing file, class, or pattern]

**Test scenarios:**
<!-- Include only categories that apply to this unit. Omit categories that don't. For units with no behavioral change, use "Test expectation: none -- [reason]" instead of leaving this section blank. -->
- [Scenario: specific input/action -> expected outcome. Prefix with category — Happy path, Edge case, Error path, or Integration — to signal intent]

**Verification:**
- [Outcome that should hold when this unit is complete]

## System-Wide Impact

- **Interaction graph:** [What callbacks, middleware, observers, or entry points may be affected]
- **Error propagation:** [How failures should travel across layers]
- **State lifecycle risks:** [Partial-write, cache, duplicate, or cleanup concerns]
- **API surface parity:** [Other interfaces that may require the same change]
- **Integration coverage:** [Cross-layer scenarios unit tests alone will not prove]
- **Unchanged invariants:** [Existing APIs, interfaces, or behaviors that this plan explicitly does not change — and how the new work relates to them. Include when the change touches shared surfaces and reviewers need blast-radius assurance]

## Risks & Dependencies

| Risk | Mitigation |
|------|------------|
| [Meaningful risk] | [How it is addressed or accepted] |

## Documentation / Operational Notes

- [Docs, rollout, monitoring, or support impacts when relevant]

## Sources & References

- **Origin document:** [docs/brainstorms/YYYY-MM-DD-<topic>-requirements.md](path)
- Related code: [path or symbol]
- Related PRs/issues: #[number]
- External docs: [url]
```

For larger `Deep` plans, extend the core template only when useful with sections such as:

```markdown
## Alternative Approaches Considered

- [Approach]: [Why rejected or not chosen]

## Success Metrics

- [How we will know this solved the intended problem]

## Dependencies / Prerequisites

- [Technical, organizational, or rollout dependency]

## Risk Analysis & Mitigation

| Risk | Likelihood | Impact | Mitigation |
|------|-----------|--------|------------|
| [Risk] | [Low/Med/High] | [Low/Med/High] | [How addressed] |

## Phased Delivery

### Phase 1
- [What lands first and why]

### Phase 2
- [What follows and why]

## Documentation Plan

- [Docs or runbooks to update]

## Operational / Rollout Notes

- [Monitoring, migration, feature flag, or rollout considerations]
```

#### 4.3 Planning Rules

- **All file paths must be repo-relative** — never use absolute paths like `/Users/name/Code/project/src/file.ts`. Use `src/file.ts` instead. Absolute paths make plans non-portable across machines, worktrees, and teammates. When a plan targets a different repo than the document's home, state the target repo once at the top of the plan (e.g., `**Target repo:** my-other-project`) and use repo-relative paths throughout
- Prefer path plus class/component/pattern references over brittle line numbers
- Keep implementation units checkable with `- [ ]` syntax for progress tracking
- Do not include implementation code — no imports, exact method signatures, or framework-specific syntax
- Pseudo-code sketches and DSL grammars are allowed in the High-Level Technical Design section and per-unit technical design fields when they communicate design direction. Frame them explicitly as directional guidance, not implementation specification
- Mermaid diagrams are encouraged when they clarify relationships or flows that prose alone would make hard to follow — ERDs for data model changes, sequence diagrams for multi-service interactions, state diagrams for lifecycle transitions, flowcharts for complex branching logic
- Do not include git commands, commit messages, or exact test command recipes
- Do not expand implementation units into micro-step `RED/GREEN/REFACTOR` instructions
- Do not pretend an execution-time question is settled just to make the plan look complete

#### 4.4 Visual Communication in Plan Documents

When the plan contains 4+ implementation units with non-linear dependencies, 3+ interacting surfaces in System-Wide Impact, 3+ behavioral modes/variants in Overview or Problem Frame, or 3+ interacting decisions in Key Technical Decisions or alternatives in Alternative Approaches, read `references/visual-communication.md` for diagram and table guidance. This covers plan-structure visuals (dependency graphs, interaction diagrams, comparison tables) — not solution-design diagrams, which are covered in Section 3.4.

### Phase 5: Final Review, Write File, and Handoff

#### 5.1 Review Before Writing

Before finalizing, check:
- The plan does not invent product behavior that should have been defined in `ce-brainstorm`
- If there was no origin document, the bounded planning bootstrap established enough product clarity to plan responsibly
- Every major decision is grounded in the origin document or research
- Each implementation unit is concrete, dependency-ordered, and implementation-ready
- If test-first or characterization-first posture was explicit or strongly implied, the relevant units carry it forward with a lightweight `Execution note`
- Each feature-bearing unit has test scenarios from every applicable category (happy path, edge cases, error paths, integration) — right-sized to the unit's complexity, not padded or skimped
- Test scenarios name specific inputs, actions, and expected outcomes without becoming test code
- Feature-bearing units with blank or missing test scenarios are flagged as incomplete — feature-bearing units must have actual test scenarios, not just an annotation. The `Test expectation: none -- [reason]` annotation is only valid for non-feature-bearing units (pure config, scaffolding, styling)
- Deferred items are explicit and not hidden as fake certainty
- If a High-Level Technical Design section is included, it uses the right medium for the work, carries the non-prescriptive framing, and does not contain implementation code (no imports, exact signatures, or framework-specific syntax)
- Per-unit technical design fields, if present, are concise and directional rather than copy-paste-ready
- If the plan creates a new directory structure, would an Output Structure tree help reviewers see the overall shape?
- If Scope Boundaries lists items that are planned work for a separate PR or task, are they under `### Deferred to Separate Tasks` rather than mixed with true non-goals?
- Would a visual aid (dependency graph, interaction diagram, comparison table) help a reader grasp the plan structure faster than scanning prose alone?

If the plan originated from a requirements document, re-read that document and verify:
- The chosen approach still matches the product intent
- Scope boundaries and success criteria are preserved
- Blocking questions were either resolved, explicitly assumed, or sent back to `ce-brainstorm`
- Every section of the origin document is addressed in the plan — scan each section to confirm nothing was silently dropped

#### 5.2 Write Plan File

**REQUIRED: Write the plan file to disk before presenting any options.**

Use the Write tool to save the complete plan to:

```text
docs/plans/YYYY-MM-DD-NNN-<type>-<descriptive-name>-plan.md
```

Confirm:

```text
Plan written to docs/plans/[filename]
```

**Pipeline mode:** If invoked from an automated workflow such as LFG, SLFG, or any `disable-model-invocation` context, skip interactive questions. Make the needed choices automatically and proceed to writing the plan.

#### 5.3 Confidence Check and Deepening

After writing the plan file, automatically evaluate whether the plan needs strengthening.

**Two deepening modes:**

- **Auto mode** (default during plan generation): Runs without asking the user for approval. The user sees what is being strengthened but does not need to make a decision. Sub-agent findings are synthesized directly into the plan.
- **Interactive mode** (activated by the re-deepen fast path in Phase 0.1): The user explicitly asked to deepen an existing plan. Sub-agent findings are presented individually for review before integration. The user can accept, reject, or discuss each agent's findings. Only accepted findings are synthesized into the plan.

Interactive mode exists because on-demand deepening is a different user posture — the user already has a plan they are invested in and wants to be surgical about what changes. This applies whether the plan was generated by this skill, written by hand, or produced by another tool.

`ce-doc-review` and this confidence check are different:
- Use the `ce-doc-review` skill when the document needs clarity, simplification, completeness, or scope control
- This confidence check strengthens rationale, sequencing, risk treatment, and system-wide thinking when the plan is structurally sound but still needs stronger grounding

**Pipeline mode:** This phase always runs in auto mode in pipeline/disable-model-invocation contexts. No user interaction needed.

##### 5.3.1 Classify Plan Depth and Topic Risk

Determine the plan depth from the document:
- **Lightweight** - small, bounded, low ambiguity, usually 2-4 implementation units
- **Standard** - moderate complexity, some technical decisions, usually 3-6 units
- **Deep** - cross-cutting, high-risk, or strategically important work, usually 4-8 units or phased delivery

Build a risk profile. Treat these as high-risk signals:
- Authentication, authorization, or security-sensitive behavior
- Payments, billing, or financial flows
- Data migrations, backfills, or persistent data changes
- External APIs or third-party integrations
- Privacy, compliance, or user data handling
- Cross-interface parity or multi-surface behavior
- Significant rollout, monitoring, or operational concerns

##### 5.3.2 Gate: Decide Whether to Deepen

- **Lightweight** plans usually do not need deepening unless they are high-risk
- **Standard** plans often benefit when one or more important sections still look thin
- **Deep** or high-risk plans often benefit from a targeted second pass
- **Thin local grounding override:** If Phase 1.2 triggered external research because local patterns were thin (fewer than 3 direct examples or adjacent-domain match), always proceed to scoring regardless of how grounded the plan appears. When the plan was built on unfamiliar territory, claims about system behavior are more likely to be assumptions than verified facts. The scoring pass is cheap — if the plan is genuinely solid, scoring finds nothing and exits quickly

If the plan already appears sufficiently grounded and the thin-grounding override does not apply, report "Confidence check passed — no sections need strengthening" and skip to Phase 5.3.8 (Document Review). Document-review always runs regardless of whether deepening was needed — the two tools catch different classes of issues.

##### 5.3.3–5.3.7 Deepening Execution

When deepening is warranted, read `references/deepening-workflow.md` for confidence scoring checklists, section-to-agent dispatch mapping, execution mode selection, research execution, interactive finding review, and plan synthesis instructions. Execute steps 5.3.3 through 5.3.7 from that file, then return here for 5.3.8.

##### 5.3.8–5.4 Document Review, Final Checks, and Post-Generation Options

When reaching this phase, read `references/plan-handoff.md` for document review instructions (5.3.8), final checks and cleanup (5.3.9), post-generation options menu (5.4), and issue creation. Do not load this file earlier. Document review is mandatory — do not skip it even if the confidence check already ran.

NEVER CODE! Research, decide, and write the plan.
