Convert between TOML and JSON via @mukundakatta/toml-mcp

@mukundakatta/toml-mcp v0.1.0 — TOML ↔ JSON bidirectional conversion

Install & run: npm install @mukundakatta/toml-mcp → entry point dist/server.js, stdio transport.

Tools (2)

Verified trace — 12 calls, 100% success, p50=1ms

to_json — simple config:

{"name":"to_json","arguments":{"text":"[server]\nhost = \"localhost\"\nport = 8080\n\n[database]\nname = \"mydb\"\nmax_connections = 10\nenabled = true"}}
→ {"value":{"server":{"host":"localhost","port":8080},"database":{"name":"mydb","max_connections":10,"enabled":true}}}

to_json — nested tables + array of tables:

{"name":"to_json","arguments":{"text":"title = \"Config\"\n\n[owner]\nname = \"Emin\"\n\n[[fruits]]\nname = \"apple\"\ncolor = \"red\"\n\n[[fruits]]\nname = \"banana\"\ncolor = \"yellow\"\n\n[database]\nports = [5432, 5433, 5434]\nconnection_max = 5000"}}
→ {"value":{"title":"Config","owner":{"name":"Emin"},"fruits":[{"name":"apple","color":"red"},{"name":"banana","color":"yellow"}],"database":{"ports":[5432,5433,5434],"connection_max":5000}}}

to_json — inline table + multiline string + date:

{"name":"to_json","arguments":{"text":"name = \"TOML Test\"\npoint = { x = 1, y = 2 }\nmultiline = \"\"\"\nline 1\nline 2\nline 3\"\"\"\ncreated = 2026-06-20T10:30:00Z"}}
→ {"value":{"name":"TOML Test","point":{"x":1,"y":2},"multiline":"line 1\nline 2\nline 3","created":"2026-06-20T10:30:00.000Z"}}

to_json — comments (stripped):

{"name":"to_json","arguments":{"text":"# This is a comment\nkey = \"value\" # inline comment\n\n[section]\n# Another comment\nnum = 42"}}
→ {"value":{"key":"value","section":{"num":42}}}

to_json — Unicode:

{"name":"to_json","arguments":{"text":"greeting = \"Merhaba dünya 🌍\"\nauthor = \"Müslüm Gürses\""}}
→ {"value":{"greeting":"Merhaba dünya 🌍","author":"Müslüm Gürses"}}

to_json — empty string: → {"value":{}} (no error)

to_json — invalid TOML: → isError: true, "toml failed: Invalid TOML document: incomplete key-value..." with line/column pointer

to_toml — simple object:

{"name":"to_toml","arguments":{"value":{"server":{"host":"localhost","port":8080},"database":{"name":"mydb","enabled":true}}}}
→ "[server]\nhost = \"localhost\"\nport = 8080\n\n[database]\nname = \"mydb\"\nenabled = true\n"

to_toml — array of tables:

{"name":"to_toml","arguments":{"value":{"title":"Config","fruits":[{"name":"apple","color":"red"},{"name":"banana","color":"yellow"}]}}}
→ "title = \"Config\"\n\n[[fruits]]\nname = \"apple\"\ncolor = \"red\"\n\n[[fruits]]\nname = \"banana\"\ncolor = \"yellow\"\n"

to_toml — deep nesting: {a:{b:{c:{d:"deep"}}}} → [a.b.c]\nd = "deep" (dotted keys)

to_toml — special values: null silently dropped; floats, negatives, empty strings preserved

Round-trip verified: to_toml({app:{name:"tani",version:"1.0"},features:["registry","exchange","governance"]}) → TOML → to_json back → identical structure

Key gotchas

1. ⚠️ `to_json` param is `text` NOT `toml` — using toml causes "Cannot read properties of undefined (reading '0')" cryptic error
2. `to_json` wraps result in `{value: ...}` — the parsed object is one level deeper than expected
3. `to_toml` returns raw TOML text — NOT JSON; read content[0].text directly, don't JSON.parse it
4. `null` values silently dropped in to_toml output (omitted, no error)
5. Dates converted to ISO 8601 strings with .000Z suffix
6. Comments stripped during parse (expected TOML spec behavior)
7. Deep nesting uses dotted keys ([a.b.c] not [a]\n[a.b]\n[a.b.c])
8. Empty object → just a newline character
9. Invalid TOML → clear error with line number and caret pointer
10. Unicode fully safe — Turkish chars, emoji preser