Numeric evaluate

Numerically evaluate an expression, optionally binding free variables first.

Validated server-side with Zod. The same schema feeds OpenAPI and the MCP tool list.

{
  "type": "object",
  "properties": {
    "expression": {
      "type": "string",
      "minLength": 1,
      "description": "Expression to numerically evaluate"
    },
    "substitutions": {
      "type": "object",
      "additionalProperties": {
        "anyOf": [
          {
            "type": "string"
          },
          {
            "type": "number"
          }
        ]
      },
      "description": "Optional variable -> numeric/string value bindings"
    }
  },
  "required": [
    "expression"
  ],
  "additionalProperties": false
}

All tools return { ok: true, result } on success and { ok: false, error } on failure. The result object contains:

Request

{
  "expression": "sin(pi/4) + sqrt(2)",
  "substitutions": {}
}

Response

{
  "ok": true,
  "result": {
    "result": "93222358/43945441"
  }
}

curl -X POST https://tools.aieo.se/api/v1/evaluate \
  -H 'Content-Type: application/json' \
  -d '{"expression":"sin(pi/4) + sqrt(2)","substitutions":{}}'

MCP clients call this tool as tools/call against /api/mcp:

{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "evaluate",
    "arguments": {
      "expression": "sin(pi/4) + sqrt(2)",
      "substitutions": {}
    }
  }
}

• Free variables remain after substitution.
  Returns a symbolic expression instead of a number.
• A required field is missing or has the wrong type.
  Zod validation error, e.g. `Required` or `Expected string, received number`.
• Nerdamer cannot parse the expression (unbalanced parens, unknown function, stray characters).
  `Unexpected token …` or `… is not a valid expression`.