Tango FAQ

Common questions about the Tango API and federal procurement sources.

Isn't there a SAM.gov and USASpending API? Can't I just use those?

Short answer: Sure, but don't say we didn't warn you.

Practical answer: Tango is an API that unifies the core procurement data sources (SAM.gov, USAspending, FPDS, DSBS, GSA eLibrary, Grants.gov, GAO bid protests, IT Dashboard, and agency forecasts) behind a single API key. It's the closest thing to a unified government contracting API. In creating it, we leveraged the federal data sources, but each data source has its own peculiarities and limitations, and it's time consuming and expensive to get the data to actually work in a way that lets you focus on shipping.

How does this compare to companies like GovWin, G2X, HigherGov, or Fedmine?

These are all great services if you need a user interface. Tango, however, is built for public-sector builders. If you are looking to work directly with the data and are comfortable with APIs, Tango is the answer you're looking for.

What's up with all of these identifiers? UEIs, USASpending keys, etc?

Each procurement system has its own different core identifiers. For example, FPDS primarily uses PIIDs for awards, whereas USASpending has its own award key format. SAM.gov uses UEIs (Unique Entity Identifier) for entities. Tango allows for you to use these identifiers to work with the authoritative data sources, while also going beyond what each individual system can provide.

How much does Tango cost?

There's a free tier. Otherwise, full pricing is on the pricing page.

How do I read the docs (or feed them to an LLM)?

The full docs live at docs.makegov.com. For programmatic / LLM consumption, we also publish:

  • The single-page HTML reference — every endpoint and concept in one document.
  • all.md — the entire docs site as one Markdown file, designed to be pasted straight into a context window.
  • The OpenAPI spec in JSON.
  • The Tango MCP server — gives Claude, Cursor, and other MCP clients direct access to Tango's search, detail, and curated fetch_api_docs tools.

What SDKs do you support?

Tango ships first-class, open-source SDKs for four languages, with parity on the API surface we expose:

For any other language, the REST API + OpenAPI spec at tango.makegov.com/api/openapi.json is enough to generate a client.

How fresh is the data in Tango?

The cadence is tuned per dataset to match how often the upstream source actually changes:

  • Opportunities (SAM.gov solicitations): every 20–60 minutes
  • Contracts & IDVs (FPDS): twice daily
  • Subawards (USAspending sub-awards): daily
  • Entities, grants, forecasts: per the upstream publication schedule (most daily; some less often)

If you need to react to changes immediately rather than poll, see the next question on webhooks.

Does Tango support webhooks?

Yes. You can subscribe to event notifications when new data lands for awards, opportunities, entities, grants, and forecasts. See the Webhooks Partner Guide for the supported event types and payload shapes.

Can I use Tango with LLMs like ChatGPT and Claude?

Absolutely yes — many of our customers do this, and we do too. For Claude, Cursor, and other MCP-compatible clients there's an official Tango MCP server that exposes Tango's discovery, search, and detail tools directly to the model. For any other LLM or agent, the REST API and the SDKs (Python, Node, Go, Rust) work the same way they would for any backend.

How do I get started?

Sign up for a free API key at tango.makegov.com.

If you have any questions, email us at hello@makegov.com.