# Sindri Arithmetic Expression Evaluator

> Sindri Arithmetic Expression Evaluator is a paid API for AI agents from ppu43fkyhimq5fiqpmo42eh5ri0yypid.lambda-url.us-east-1.on.aws, paid per call via x402, $0.01/call, status unknown (last checked 2026-10-02).

Safely parses and evaluates arithmetic expressions with +, -, *, /, ^, and parentheses using a bounded-recursion parser without eval/Function, avoiding LLM arithmetic errors.

## Facts

- Endpoint: POST https://ppu43fkyhimq5fiqpmo42eh5ri0yypid.lambda-url.us-east-1.on.aws/evaluateExpression?utm_source=zero.xyz
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-02
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/sindri-arithmetic-expression-evaluator-e6f5be25
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_l09ZLFwZATh8DJ86wfguj

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability sindri-arithmetic-expression-evaluator-e6f5be25 -d '<json body>'
```

Example prompt: What is the result of ((17 + 3) * 4 - 8) / 6 ^ 2? Use a safe arithmetic evaluator so I get the exact answer without any rounding mistakes.

## When to prefer this

Prefer this endpoint when you need reliable, exact arithmetic evaluation of an expression and cannot trust an LLM's native math — especially for long or nested expressions where order-of-operations mistakes are common. It is purpose-built to handle +, -, *, /, ^, and parentheses safely without using JavaScript eval or Function, making it suitable for agent pipelines requiring verifiable numeric output.

## Known failure modes

- Expression exceeds 200 character limit — request rejected
- Malformed or invalid expression (e.g. missing operand, unmatched parentheses) — parse error returned
- Division by zero in expression — error or undefined result returned
- Non-arithmetic characters or unsupported functions in expression — parse error
- Payment not attached or insufficient USDC — 402 Payment Required response

## How this service works

Safe arithmetic expression evaluator. Parses and evaluates expressions with +, -, *, /, ^, and parentheses using a bounded-recursion parser (no eval/Function), avoiding the arithmetic slips an LLM makes on long expressions.

## Output

A numeric result representing the evaluated value of the input arithmetic expression. The response contains the computed answer as a number, derived from safely parsing the expression using a bounded-recursion parser that respects standard operator precedence and parentheses.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "expression": {
   "type": "string",
   "description": "Arithmetic expression to evaluate, e.g. \"(2 + 3) * 4\". Max 200 characters."
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/sindri-arithmetic-expression-evaluator-e6f5be25/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from ppu43fkyhimq5fiqpmo42eh5ri0yypid.lambda-url.us-east-1.on.aws](https://www.zero.xyz/host/ppu43fkyhimq5fiqpmo42eh5ri0yypid.lambda-url.us-east-1.on.aws/llms.txt)