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Free / no key
Math calculator
Use this when customers ask for calculations (totals, percentages, simple formulas). The agent sends the expression to the public mathjs API and returns the result.
Setup
- Open Create agent or Edit agent and add a custom tool.
- Copy the fields below into the form. No API key is required.
- Optionally mention evaluate_math in your prompt when the customer needs a calculation.
Copy into custom tool form
Copy each value into the matching field when you add a custom tool on the create or edit agent page. Replace any YOUR_… placeholders with your real credentials.
Tool name
evaluate_math
Description
Evaluate a math expression when the customer asks for a calculation. Use this for arithmetic, percentages, unit-style expressions supported by mathjs.
Endpoint URL
Paste into Endpoint URL (https:// is added automatically).
api.mathjs.org/v4/
HTTP method
GET
Tool inputs (all)
1. expression (string)
Math expression to evaluate, e.g. 2*(3+4) or 15% of 80 as 0.15*80
Tool input: expression
Input name
expression
Input type
string
Input description
Math expression to evaluate, e.g. 2*(3+4) or 15% of 80 as 0.15*80
Reference value
Use this as the request query or body value and choose “Tool input” in the form.
{{expression}}
Request query (all)
expr: {{expression}}
Field name
expr
Field value
{{expression}}