# tabnas (slim)

> tabnas, an MCP server by tabnas.dev, listed from the official MCP registry. Indexed, not reviewed: facts and our own checks, no score or ranking. Seven tools over the tabnas parsing engine: parse, validate, diagnose, fixtures, compare.

- Full: https://www.anchorterminal.com/tools/tabnas-mcp.md (~1,050 tokens) · this version ~980 tokens · JSON https://www.anchorterminal.com/tools/tabnas-mcp.json · canonical https://www.anchorterminal.com/tools/tabnas-mcp
- Index: https://www.anchorterminal.com/llms.txt · API: https://www.anchorterminal.com/api/v1/index.json · Updated: 2026-10-05

# tabnas

> Indexed, not reviewed: facts from the official MCP registry and our own checks. No score, grade or rank, and not in the rankings until the panel reviews it. How the index works: https://www.anchorterminal.com/indexed/

- Kind: MCP server, by tabnas.dev (https://tabnas.dev/mcp)
- Listed because: It's published in the registry under tabnas.dev, a namespace the registry only gives to whoever proves they control that domain.
- What the official MCP registry says: Seven tools over the tabnas parsing engine: parse, validate, diagnose, fixtures, compare.

## Facts

- MCP registry: `dev.tabnas/mcp` 0.1.17
- Endpoint: https://mcp.tabnas.dev/mcp (streamable HTTP)
- Package: npm `@tabnas/mcp` (stdio)
- Source: https://github.com/tabnas/mcp
- Website: https://tabnas.dev/mcp
- npm downloads a week: 174
- GitHub stars: 0
- Registry entry updated: 2026-10-03

## Tools

- Tools it lists (7, about 1,410 tokens of context, `tools/list` without credentials, checked 2026-10-04 22:24 UTC):
  - `parse`: Parse input with the tabnas engine. Returns {ok:true, tree} or, on parse failure, {ok:false, diagnostic} — the structured diagnostic described by resource…
  - `validate_grammar`: Validate a serialized GrammarSpec. Structural validation against the bundled grammar schema, an engine load in a fresh instance, and a check that every rule…
  - `explain_parse_error`: Parse input and explain the failure. Returns {failed:false} when the input parses; otherwise {failed:true, diagnostic, registry} where registry is the…
  - `test_grammar`: Run TSV fixture content against a grammar in a fresh instance, using the fleet fixture convention (@tabnas/support): line 1 is a header, the input column is…
  - `list_plugins`: List every bundled tabnas plugin descriptor (tabnas.plugin.json of each fleet repo), sorted by name. Returns {plugins:[...]}.
  - `describe_plugin`: The full descriptor for one plugin, by package name ('@tabnas/csv') or bare fleet name ('csv'). Unknown names get {ok:false, errors} naming the known plugins.
  - `compare_grammars`: Grammar compatibility (AX plan Phase 5): does candidate grammar B still accept what baseline A accepted, and does it build the same tree for inputs both…
- How its tools read to an agent (0 errors, 13 warnings, 1 note, about 1,410 tokens; rules at https://www.anchorterminal.com/check.md; not part of the score):
  - warn TC11 test_grammar: 1 parameter without a description: options
  - warn TC13 compare_grammars: a (object with no properties), b (object with no properties), options (object with no properties)
  - warn TC13 explain_parse_error: grammar (object with no properties)
  - warn TC13 parse: grammar (object with no properties), options (object with no properties)
  - warn TC13 test_grammar: grammar (object with no properties)
  - warn TC13 validate_grammar: grammar (object with no properties)
  - warn TC16 compare_grammars: no readOnlyHint or destructiveHint
  - warn TC16 describe_plugin: no readOnlyHint or destructiveHint
  - warn TC16 explain_parse_error: no readOnlyHint or destructiveHint
  - warn TC16 list_plugins: no readOnlyHint or destructiveHint
  - warn TC16 parse: no readOnlyHint or destructiveHint
  - warn TC16 test_grammar: no readOnlyHint or destructiveHint
  - warn TC16 validate_grammar: no readOnlyHint or destructiveHint
  - note TC24 server: 7 of 7 tools have no outputSchema

- JSON: https://www.anchorterminal.com/api/v1/tools/tabnas-mcp.json
- Being indexed says nothing about quality, and nobody can pay for it. Ask for a review: https://www.anchorterminal.com/builders/#claiming