# math_eval

Evaluates arithmetic with correct operator precedence, parentheses, exponentiation, factorials, named variables and 30+ functions. Language models perform arithmetic by pattern-matching and quietly get long multiplications and compounding wrong; this computes the number instead of predicting it.

Agent View of the PolicyLayer registry record for `math_eval`. HTML page: https://policylayer.com/tools/com-fluentedi-tools/math-eval

## Facts

- Tool: `math_eval`
- Server: Tools (`https://fluentedi.com/mcp`) — https://policylayer.com/tools/com-fluentedi-tools.md
- Homepage: https://github.com/https://fluentedi.com/mcp
- Risk category: Read (Low risk)
- Registry record: grade F, identity unverified
- Server auth posture: open
- Server CORS policy: *
- Server rate-limited: no
- Parameters: 3 (1 required)
- Recommended policy verdict: Allowed

## Parameters

| Parameter | Type | Required | Description |
| --- | --- | --- | --- |
| `precision` | integer | no | Decimal places to round the formatted result to. |
| `variables` | object | no | Named values usable in the expression, e.g. {"rate": 0.07}. |
| `expression` | string | yes | Expression to evaluate, e.g. "(1+0.07)^30 * 1000". |

Parameters from the server's own tool schema.

## Example call (MCP tools/call, JSON-RPC 2.0)

```json
{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "math_eval",
    "arguments": {
      "expression": "<expression>"
    }
  }
}
```

## Why math_eval is rated Low

Even though math_eval only reads data, uncontrolled read access leaks sensitive information and racks up API costs: an agent caught in a retry loop can make thousands of calls a minute without anyone noticing.

Risk signals: Accepts freeform code/query input (expression)

## Use case

AI agents call math_eval to retrieve information from Tools without modifying anything. It is typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.

## Recommended policy (PolicyLayer)

Verdict: **Allowed**. Enforced by the PolicyLayer MCP gateway (https://policylayer.com/mcp-gateway) before a call reaches Tools:

```json
{
  "version": "1",
  "default": "deny",
  "tools": {
    "math_eval": {}
  }
}
```

## Other tools on Tools (16)

- `cron_next` — Execute — https://policylayer.com/tools/com-fluentedi-tools/cron-next.md
- `edi_build` — Execute — https://policylayer.com/tools/com-fluentedi-tools/edi-build.md
- `edi_parse` — Execute — https://policylayer.com/tools/com-fluentedi-tools/edi-parse.md
- `edi_validate` — Read — https://policylayer.com/tools/com-fluentedi-tools/edi-validate.md
- `hash` — Read — https://policylayer.com/tools/com-fluentedi-tools/hash.md
- `http_assert` — Read — https://policylayer.com/tools/com-fluentedi-tools/http-assert.md
- `http_check` — Read — https://policylayer.com/tools/com-fluentedi-tools/http-check.md
- `json_query` — Read — https://policylayer.com/tools/com-fluentedi-tools/json-query.md
- `json_repair` — Read — https://policylayer.com/tools/com-fluentedi-tools/json-repair.md
- `time_diff` — Read — https://policylayer.com/tools/com-fluentedi-tools/time-diff.md
- `time_now` — Read — https://policylayer.com/tools/com-fluentedi-tools/time-now.md
- `time_window` — Read — https://policylayer.com/tools/com-fluentedi-tools/time-window.md
- `tool_describe` — Read — https://policylayer.com/tools/com-fluentedi-tools/tool-describe.md
- `tool_search` — Read — https://policylayer.com/tools/com-fluentedi-tools/tool-search.md
- `time_convert` — Write — https://policylayer.com/tools/com-fluentedi-tools/time-convert.md
- `tool_call` — Write — https://policylayer.com/tools/com-fluentedi-tools/tool-call.md

## For agents

This record is a snapshot. Live verdicts and the full registry:

- Check every server in your MCP config at once: `npx -y policylayer stack`
- Vet a server before you add it: install the mcp-precheck skill — `npx skills add https://policylayer.com` (skill text: https://policylayer.com/skill.md)
- Query the registry over MCP: endpoint `https://api.policylayer.com/mcp` — tools `check_mcp_server`, `check_mcp_stack`, `check_tool`, `search_registry`, `get_change_events`

---

Source: the PolicyLayer MCP registry — one continuously verified record per MCP server. Full record: https://policylayer.com/registry?q=com-fluentedi-tools · API: https://policylayer.com/registry/api · Policy library: https://policylayer.com/policies/com-fluentedi-tools