Concepts

• Authentication

  API keys and connected apps (OAuth sign-in), what each is for, how to send them and where to revoke them.

• Limits and quotas

  Daily calls per key, keys per account, one call at a time, the X-Quota-Remaining header and what a 429 means.

• Errors

  Every status the API returns, the JSON shape of an error, how MCP reports the same failures and when to retry.

• Credits

  How Fundalyze credits work, what spends them, and why nothing is blocked by them today.

• Data sources and attribution

  Where every figure comes from, which sources are left out, and how to credit the data when you show it to others.

• Changes and versioning

  What can change in the API without notice, what counts as a breaking change, and where changes are announced.

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