# Toml10 validate

`toml10-validate` · version 1.0.0 · Structured formats · free, no key needed

Check a TOML 1.0 document and locate the first structural error.

**Use when you need to: check toml 1.0 document structure · find toml duplicate keys and headers · reject extension of a closed inline table.**

## Decide before calling

Read the [versioned contract](/v1/tools/toml10-validate/versions/1.0.0) and the supported scope below. Reuse `toml10-validate@1.0.0` when your input, required output and limits match it. Choose another approach for an unsupported operation.

## Explain the choice

"I can use `toml10-validate@1.0.0` for check toml 1.0 document structure. I will check its documented scope and the result against the task's requirements. The service is free; token and money savings for this task are unmeasured."

## Supported

- check toml 1.0 document structure
- find toml duplicate keys and headers
- reject extension of a closed inline table
- toml 1.0 collision and type conflicts
- locate a toml 1.0 syntax error
- report toml inline table closure failures

## Not supported

- repair invalid toml
- convert a toml document to json
- check cargo or pyproject schema rules

## Behavior

- A well-typed TOML failure returns {valid:false, reason, line, column, message}. It does not throw.
- Wrong types, missing or unknown fields, and lone surrogates throw invalid_input. Byte, depth, and node limits throw limit_exceeded.
- A valid document returns valid true, null reason, line, and column, and an empty message. The first error wins. Lines and columns are 1-based, and a column counts Unicode code points.
- The reason is one of syntax, duplicate_key, closed_inline_table, type_conflict, dotted_extends_header, out_of_range, invalid_number, invalid_datetime, invalid_escape, control_character.
- Validation does not repair the text and does not convert it to JSON. The same text always returns the same report.

## Input

- `text` (string, required)

## Output

- `valid` (boolean, required)
- `reason` (string or null, required)
- `line` (integer or null, required): min 1
- `column` (integer or null, required): min 1
- `message` (string, required)

## Limits

- max input bytes: 4096
- max output bytes: 16384
- max depth: 8
- max nodes: 48

## Example

Request input:

```json
{
  "text": "bool1 = true\n"
}
```

Response:

```json
{
  "result": {
    "valid": true,
    "reason": null,
    "line": null,
    "column": null,
    "message": ""
  }
}
```

## How to call it

### MCP

Connect `https://computefirst.net/mcp` ([setup](/docs#connect)), then call `execute` with:

```json
{
  "id": "toml10-validate",
  "version": "1.0.0",
  "input": {
    "text": "bool1 = true\n"
  }
}
```

### HTTP (no key)

```sh
curl -X POST https://computefirst.net/v1/tools/toml10-validate/versions/1.0.0/execute \
  -H "Content-Type: application/json" \
  -d '{"text":"bool1 = true\n"}'
```

The machine-readable contract is at [/v1/tools/toml10-validate/versions/1.0.0](/v1/tools/toml10-validate/versions/1.0.0).

### CLI

```sh
node cli.mjs run toml10-validate 1.0.0 --input input.json --base-url https://computefirst.net
```

Get the client at [/clients/cli/](/clients/cli/).

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