pantheon-ai/implementation-planner
Converts a PRD or requirements document into a structured, phased implementation plan with individual phase files and granular per-task files written to .context/plans/. Also restructures existing monolithic planning documents into digestible, hierarchical directory structures. Creates a root plan index summarising all phases, a numbered phase file per phase, and a numbered task file per task inside each phase directory.
92
93%
Does it follow best practices?
Impact
91%
3.25xAverage score across 5 eval scenarios
Passed
No known issues
Evaluation results
99%
95%Task: Create an implementation plan for a URL Shortener service
create-new-plan-from-prd
plan-root-created
0%
100%
root-readme-is-index-only
0%
100%
phases-directory-structure
0%
100%
phase-readme-has-goal-gate-deps
0%
100%
gate-is-concrete-not-vague
0%
100%
tasks-directory-exists-per-phase
0%
100%
task-identifier-format-correct
0%
100%
task-files-have-verification-section
0%
100%
task-verification-not-vague
0%
100%
tasks-scoped-to-single-file
0%
100%
slug-format-correct
25%
100%
scripts-used-for-scaffolding
0%
100%
validate-plan-script-run
0%
100%
completion-summary-reported
0%
75%
additive-no-deletion
100%
100%
reasonable-phase-count
0%
100%
95%
20%Task: Restructure a flat planning document into a navigable hierarchy
restructure-monolithic-plan-into-hierarchy
output-under-correct-path
100%
100%
each-phase-has-directory
100%
100%
no-numeric-only-directory-names
100%
100%
no-generic-vague-names
100%
62%
every-directory-has-readme
100%
100%
leaf-files-have-required-sections
20%
100%
flatten-vs-subdivide-heuristics-applied
100%
75%
numbering-prefix-grouping-respected
100%
100%
source-not-deleted-before-validation
50%
100%
validate-structure-script-run
0%
100%
readme-links-resolve
100%
100%
max-depth-respected
100%
100%
activities-or-steps-subdirectory
0%
100%
readme-minimum-content
100%
100%
kebab-case-names
100%
100%
97%
90%Task: Create an implementation plan for an E-commerce Checkout Redesign
naming-conventions-slug-and-identifier-compliance
plan-slug-is-kebab-case
0%
100%
phase-slugs-are-kebab-case
0%
100%
task-identifier-format-all-files
0%
100%
task-numbering-starts-at-01
0%
100%
task-numbering-sequential-no-gaps
0%
100%
phase-numbering-sequential-no-gaps
0%
100%
no-spaces-or-underscores-in-slugs
66%
100%
phase-and-task-zero-padding-two-digits
0%
100%
task-slug-after-identifier-is-descriptive
0%
100%
root-readme-is-index
0%
100%
phase-readmes-include-goal-gate
0%
100%
validate-plan-run
0%
100%
completion-summary-includes-paths
20%
40%
slug-length-reasonable
100%
100%
70%
64%Task: Create an implementation plan for a large-scale SaaS platform
large-scope-phase-count-guardrail
scope-analysis-performed
25%
100%
user-asked-before-exceeding-8-phases
0%
0%
question-is-specific-not-generic
0%
100%
no-plan-created-without-answer
0%
100%
plan-within-8-phases-if-user-not-asked
0%
0%
root-readme-is-navigation-index
0%
100%
phase-readmes-have-gates
0%
100%
task-identifiers-correct-format
0%
100%
task-verification-sections-present
0%
100%
scripts-used-for-scaffolding
0%
100%
validate-plan-run-if-files-created
0%
100%
slug-format-correct
100%
100%
97%
45%Task: Add a new phase to an existing implementation plan
task-isolation-and-verification-quality
phase-03-directory-created
100%
100%
existing-phases-untouched
100%
62%
phase-readme-has-gate
0%
100%
task-count-matches-scope
100%
100%
task-ids-continue-sequence
0%
100%
task-scoped-to-single-handler
87%
100%
task-verification-is-runnable
0%
100%
no-vague-verification
62%
100%
dependencies-declared
100%
100%
scaffold-scripts-used
0%
100%
validate-plan-run
0%
100%
root-readme-updated
100%
100%
slug-format-correct
100%
100%
completion-summary-reported
50%
100%
- Evaluated
- Agent
- Claude
- Model
- Claude Sonnet 4.5
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