# Gradient Dynamics

> Gradient Dynamics lets engineers and AI agents design and simulate cooling hardware: GPU-native CFD and conjugate heat transfer (CHT) for cold plates, heat sinks, battery packs and electronics, returning temperatures, pressure drops and interactive 3D results. Agents connect to the remote MCP server at https://api.gradient-dynamics.com/mcp (Streamable HTTP) or the REST API at https://api.gradient-dynamics.com/v1. They can list templates, read schemas and estimate cost without an account (when enabled), then sign in through OAuth or device login, or use an API key. Every connection carries a spending budget a person sets (default 20 credits a month), and unfunded runs return HTTP 402 with a top-up link instead of running.

The usual agent workflow is:

1. choose a template or upload STEP/STL;
2. inspect the geometry for real component, zone and patch names;
3. estimate the cost (`estimate_cost`);
4. mesh (`create_mesh`, structured or OpenFOAM, up to 20 million cells);
5. simulate (`run_simulation`: steady RANS, URANS or CHT on GPUs);
6. read the convergence and quality flags and view the results.

Meshing and simulation are charged by measured GPU time. Browsing, schemas and estimates are free. Uploaded CAD is stored by Gradient Dynamics, and your agent sees summaries and IDs, not raw geometry files.

## Connect

- [Connect from Claude](https://docs.gradient-dynamics.com/connect/from-claude.html): Claude app and Desktop custom connector, Claude Code (`claude mcp add --transport http …`), OAuth or API key
- [Connect from Cursor](https://docs.gradient-dynamics.com/connect/from-cursor.html): `mcp.json` with OAuth login or a Bearer header
- [Connect from Codex or ChatGPT](https://docs.gradient-dynamics.com/connect/from-codex.html): `~/.codex/config.toml` with `codex mcp login`, or a ChatGPT custom MCP server
- [Connect headless agents and CI](https://docs.gradient-dynamics.com/connect/headless.html): API keys, `gd login` device flow, idempotency and stopping on refusals

## Docs

- [Quick-start: simulate a cold plate](https://docs.gradient-dynamics.com/connect/quick-start-cold-plate.html): end-to-end CHT workflow with real tool names, estimate-before-run and budgets
- [Plans, limits and budgets](https://docs.gradient-dynamics.com/reference/subscription-tiers.html): credits, the Core free trial, Developer (£10 a credit), Core, cell limits, 402 error codes
- [Data handling](https://docs.gradient-dynamics.com/connect/data-handling.html): where uploads go, what the AI model sees, retention, training, deletion
- [MCP tool reference](https://docs.gradient-dynamics.com/connect/mcp-tools.html): every tool with its purpose, scope, read-only/destructive annotation and whether it needs sign-in

## API

- [REST API reference (OpenAPI)](https://api.gradient-dynamics.com/openapi.json): `/v1` endpoints for projects, geometry, meshes, simulations, jobs, artifacts and estimates
- [MCP server metadata](https://gradient-dynamics.com/.well-known/mcp/server.json): `com.gradient-dynamics/engineering` registry entry (`server.json`)
- [OAuth protected resource metadata](https://api.gradient-dynamics.com/.well-known/oauth-protected-resource/mcp): how MCP clients discover sign-in (when enabled)

## Optional

- [Gradient Dynamics website](https://gradient-dynamics.com/): company, products and validation studies
- [Gradient Dynamics Studio](https://studio.gradient-dynamics.com/): sign-up, API keys (Studio → Developer), connected apps, billing
- [Documentation](https://docs.gradient-dynamics.com/): the full product documentation