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Build your own personal finance app

Build custom apps, dashboards, and agents on top of Cobalt.

Build whatever you want on top of your financial data.

Account linking happens in Cobalt

You cannot link banks or brokerages from your own app. Institution connections (Plaid, OAuth providers) live in the Cobalt web and mobile apps for security and compliance reasons.

What you can do from your app:

  • Read all accounts, transactions, positions, balances, tags.
  • Create and update manual accounts and transactions.
  • Tag, categorize, analyze, visualize.

Tell users to connect their banks once at cobaltpf.com or in the mobile app. Your app reads from that.

Prompt for your favorite LLM

Paste this into Claude, ChatGPT, Cursor, or whichever LLM you use. Fill in {{IDEA}} with the app you want.

Build me a personal finance app: {{IDEA}}

Use the Cobalt TypeScript SDK (@cobalt-money/sdk) on top of my Cobalt account data.

Stack:
- Next.js (App Router) + TypeScript
- Tailwind CSS
- @cobalt-money/sdk for all data access

Setup:
- API key from Cobalt app: profile icon → Account → Developer → API Keys → Create Key (prefix ck_live_)
- Store in COBALT_API_KEY env var, server-side only
- Initialize the SDK on the server, never ship the key to the browser

Constraints:
- Do NOT attempt to link banks or brokerages — that happens in the Cobalt app, not here
- Manual accounts and transactions ARE allowed via the SDK
- All endpoints return { data, error } — handle both branches
- Server components / route handlers for reads; client components only for UI

Reference docs:
- SDK: https://docs.cobaltpf.com/docs/sdk
- API: https://docs.cobaltpf.com/docs/api-reference
- OpenAPI: https://api.cobaltpf.com/v1/openapi.json

Start by listing the user's accounts and transactions, then build {{IDEA}} on top.

Surfaces

@cobalt-money/sdk — typed client. → SDK docs

REST API — direct HTTP. → API reference

MCP — connect AI agents instead of writing app code. → MCP docs

Auth

All surfaces use the same ck_live_* API keys. Issue from the Cobalt app: profile icon → Account → Developer → API Keys → Create Key. Server-side only — never ship in client bundles.

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