---
title: "Compare 2–5 materials side-by-side on mechanical, thermal, and process properties."
method: POST
path: "/tools/compare_materials"
---

# Compare 2–5 materials side-by-side on mechanical, thermal, and process properties.

`POST /tools/compare_materials`

## Request

- Base URL: `https://api.mechanofab.com/v1`
- URL: `https://api.mechanofab.com/v1/tools/compare_materials`
- Auth: HTTP bearer

Use when the user asks to compare materials (e.g. 'AL6061 vs SS304', 'which plastic is stronger'). Returns a structured comparison table grouped by property. Accepts 2–5 material IDs and an optional list of properties to compare.

## Request body

- object
  - `material_ids` string[], required: List of Material_IDs to compare
  - `properties` string[]: Optional: which properties to include. Defaults to density, tensile, yield, max_temp, cost_tier.

## Response `200`

Tool result

- object
  - `comparison_table` unknown[], required
    - unknown
  - `winner` string, required
  - `notes` string, required
  - `source_tag` string, required

## Other responses

- `400`: Invalid request/input.
- `401`: Missing/invalid credentials.
- `402`: Insufficient credits.
- `403`: Scope/tool forbidden.
- `404`: Unknown resource.
- `409`: Idempotency conflict.
- `429`: Rate limited.
- `503`: Control plane / runtime unavailable.

---

[API](https://skmtc.dev/mechanofab/apis/mechanofab-api.md) · [All operations](https://skmtc.dev/mechanofab/apis/mechanofab-api/llms.txt) · [OpenAPI document](https://skmtc.dev/mechanofab/apis/mechanofab-api/revisions/5945a6fad621?raw)