Claude-skill-registry doc-forms

Reference for The Fold's typed comments and doc forms system. Use when adding type annotations, documentation, todos, or other metadata to Scheme code. Covers (doc ...) syntax, standard tags, search commands, and type checker integration.

install

source · Clone the upstream repo

git clone https://github.com/majiayu000/claude-skill-registry

Claude Code · Install into ~/.claude/skills/

T=$(mktemp -d) && git clone --depth=1 https://github.com/majiayu000/claude-skill-registry "$T" && mkdir -p ~/.claude/skills && cp -r "$T/skills/data/doc-forms" ~/.claude/skills/majiayu000-claude-skill-registry-doc-forms && rm -rf "$T"

manifest: skills/data/doc-forms/SKILL.md

Doc Forms (Typed Comments)

The Fold uses

(doc ...)

forms for searchable, introspectable annotations that survive in source code.

Basic Syntax

Contextual (belongs to enclosing definition)

(define (add x y)
  (doc 'type (-> Int Int Int))
  (doc 'description "Adds two numbers")
  (+ x y))

Targeted (names what it documents)

(doc factorial 'type (-> Int Int))
(define (factorial n)
  (if (= n 0) 1 (* n (factorial (- n 1)))))

Semantics

Property	Behavior
Arguments	NOT evaluated (pure metadata)
Return value	`void` — use in sequences, not value positions
Normalization	Stripped — code with/without docs hashes identically
Extraction	Tooling reads from source ( `lf-todo` , `lf-types` )
Type authority	Authoritative — `(doc f 'type ...)` takes precedence over inference

Standard Tags

Tag	Purpose	Example
`'type`	Type signature	`(doc 'type (-> Int Int))`
`'description`	Human-readable description	`(doc 'description "Adds two numbers")`
`'param`	Parameter documentation	`(doc 'param 'x "The first operand")`
`'returns`	Return value description	`(doc 'returns "The sum")`
`'todo`	Work to be done	`(doc 'todo "Optimize for large inputs")`
`'fixme`	Known issue	`(doc 'fixme "Edge case with negative numbers")`
`'deprecated`	Deprecation notice	`(doc 'deprecated "Use add-safe instead")`
`'since`	Version introduced	`(doc 'since "1.2.0")`
`'see`	Related items	`(doc 'see 'subtract)`
`'note`	Implementation note	`(doc 'note "Uses memoization internally")`

Search Commands

After loading

lattice/meta/docs.ss

(lf-todo)           ; Find all todos in codebase
(lf-types)          ; Find all type annotations
(docs-for 'symbol)  ; Find docs for specific target
(doc-stats)         ; Count docs by tag

Type Checker Integration

Doc type annotations integrate with both the LSP and type inference:

Component Behavior

LSP hover Shows doc-declared types with highest priority

Type inference

Uses declared types via

lookup-declared-type

core/types/infer.ss

Bridge

load-doc-types-into-checker!

populates type checker from doc index

Example: Declaring Types for Inference

;; The type checker will trust this annotation
(doc my-complex-fn 'type (-> (List Int) (Maybe Int)))
(define (my-complex-fn lst)
  ;; Complex implementation...
  )

Todos vs BBS Issues

Use Case	When to Use
`(doc 'todo ...)`	Colocated with code, for localized improvements (performance, refactoring, cleanup)
BBS issue	Tracked work items, features, bugs, cross-cutting concerns, things needing scheduling

Rule of thumb: If it needs to be scheduled or tracked across sessions, use BBS. If it's a note-to-self next to the code, use

(doc 'todo ...)

Examples

Full Function Documentation

(define (binary-search vec target)
  (doc 'type (-> (Vector Int) Int (Maybe Int)))
  (doc 'description "Binary search for target in sorted vector")
  (doc 'param 'vec "Sorted vector of integers")
  (doc 'param 'target "Value to find")
  (doc 'returns "Index wrapped in Just, or Nothing if not found")
  (doc 'todo "Add bounds checking")
  ;; implementation...
  )

Deprecation

(doc old-api 'deprecated "Use new-api instead. Will be removed in 2.0")
(define (old-api x) (new-api x))

Module-Level Documentation

;; At top of file
(doc 'description "Matrix operations for linear algebra")
(doc 'since "1.0.0")
(doc 'see 'linalg/vec)