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Developer Platform / API Design

Design a new tool or improvement for a public API surface, as if a third-party developer will depend on it.

The problem

We run a public MCP (Model Context Protocol) server used by AI clients like Claude, ChatGPT and Cursor to pull Indian market data. Every tool we ship is a contract — a third party is going to call it without reading our source.

Good platform design here means anticipating misuse, rate limits, versioning and error semantics up front, not retrofitting them after the first breaking change.

What to deliver

  • A design (and working prototype, if you have time) for a new tool or a meaningful improvement to an existing public API surface — ours or one you design from scratch in the same domain.
  • Explicit API documentation good enough that a developer could integrate without asking you a question.
  • A stance on authentication, rate limiting and error handling for the endpoint you're designing.
  • A versioning/deprecation plan — what happens when you need to change this later without breaking existing integrators?

What a good submission looks like

  • Reads like something written for a stranger, not for yourself — clear inputs, outputs, error cases.
  • Anticipates abuse and edge cases (empty results, invalid symbols, rate-limit exhaustion) explicitly.
  • Has an opinion on versioning before it's needed, not after the first breaking change.

We're evaluating

API ergonomicsDocumentation clarityAuth & rate-limit thinkingVersioning sense

How to submit

  1. Build your solution, using any tools or stack you prefer.
  2. Write up your thinking — decisions made, tradeoffs, what you'd do with more time.
  3. Zip your code + write-up, name it yourname-dev-platform.zip.
  4. Email it to us — the button below pre-fills the subject and a template.