API reference

HTML entities: Encode

Escape text for HTML.

GET POST /api/html/encode MCP tool html_encode

minimal escapes & < > " ', which is sufficient inside element content and quoted attributes. ascii additionally writes every non-ASCII code point as &#x…;.

Browser version (runs locally): HTML Entities.

Try it
Credentials
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POST /api/html/encode with a JSON body

Parameters

Parameter Type Default Description
input required string — Text to convert. As a text/plain POST body it is used verbatim.
mode minimal | ascii minimal minimal: Escapes only & < > " ' — safe for HTML text and attributes. ascii: Minimal, plus every non-ASCII character as a numeric entity (&#x…;)

Also accepted on every endpoint: format (json | text). Parameters may come from the query string, a JSON object body, an urlencoded or multipart form, or (for input) a text/plain body.

Global parameters
Parameter Type Default Description
format json | text json json returns the documented object. text returns only the primary value as text/plain (see "Text output").

Response 200 application/json

Field Type Description
operation "encode" The direction performed.
mode "minimal" | "ascii" The mode used (the default if none was given).
output string The converted text.

Text output (format=text, text/plain): The converted text only.

Errors

Errors are JSON: {"error": "<message>", "code": "<code>", "param": "<name>"?}.

Status Code When
400 missing_parameter A required parameter is absent.
400 unknown_parameter A parameter name is not in the table above (typos are rejected, not ignored).
400 invalid_parameter A value has the wrong type, is out of range, or is not an allowed value.
413 payload_too_large The request body exceeds 1 MiB.
405 method_not_allowed A method other than GET, POST or OPTIONS.

Behaviour

  • Idempotent: the same arguments always return the same result.
  • Requires a client ID and secret (authentication). Each call is recorded as one metadata row against your client ID; inputs and outputs are never stored or logged. Responses carry cache-control: no-store.
  • CORS: any origin may call this endpoint from a browser, using your credentials.

Examples

Responses below were produced by running each request through this code at build time. Long strings are shortened.

Escape markup

curl 'https://util.caruana.me/api/html/encode?input=%3Ca%20href%3D%22x%22%3ETom%20%26%20Jerry%3C%2Fa%3E'

Response 200

{
  "operation": "encode",
  "mode": "minimal",
  "output": "&lt;a href=&quot;x&quot;&gt;Tom &amp; Jerry&lt;/a&gt;"
}
Same call as an MCP tools/call
{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "html_encode",
    "arguments": {
      "input": "<a href=\"x\">Tom & Jerry</a>"
    }
  }
}