catalog / formats

TOML

A configuration format designed to be unambiguous — including the parts that catch people.

16 capabilities 6 sections reference specification

Build against it

# give your agent the catalog — no account, no install
claude mcp add provespec -- npx -y provespec-mcp

# then, from any agent session
spec_get(slug: "toml")                → the capability tree
spec_checklist(slug: "toml")          → the questions to answer
spec_grade(slug: "toml", grades: [...])  → parity % + the gap list

# or just fetch it
curl https://provespec.com/catalog/toml/spec.json

Grade every capability below as yes · partial · no · na, with a file reference as evidence. Whatever you leave ungraded counts as missing — the gap list is the work queue.

Or just paste this to your agent

Use the ProveSpec MCP server. Fetch the "toml" spec with
spec_get, then walk spec_checklist and grade this repository against it —
one verdict per capability, each with a file reference as the note.
Call spec_grade with the results and give me the gap list as the plan.

If the server is not registered, add it first:
  claude mcp add provespec -- npx -y provespec-mcp

The specification

Grammar 4

  • Key/value pairs with bare, quoted and dotted keys
  • Tables and nested tables [a.b]
  • Array of tables [[a]] the feature most parsers get wrong
  • Inline tables, single line only { a = 1 }

Types 5

  • Strings: basic, literal, multi-line escape rules differ per kind
  • Integers and floats with underscores and special values inf, nan
  • Booleans lowercase only
  • Offset date-time, local date-time, date, time first-class, not strings
  • Arrays, heterogeneous allowed in 1.0

Rules 3

  • Keys cannot be redefined duplicate key is an error
  • Tables cannot be reopened once closed
  • UTF-8 input, no BOM required

Errors 1

  • Line, column and the rule violated

Round-trip 2

  • Emit valid TOML that reparses to the same value
  • Comment and ordering preservation when asked

Conformance 1

  • Passes the toml-test suite valid and invalid cases
Download spec.json All 85 specs