gsa-calc

GSA CALC+ ceiling labor rates — the maximum hourly price a vendor may charge the US government for a labor category under a GSA schedule contract. Used to benchmark rates before negotiating.

Part of Pipeworx — an MCP gateway connecting AI agents to 1573+ live data sources.

Tools

Tool	What it answers
gsa_labor_rates	"What do senior software engineers bill under MAS?" — individual rates with vendor, contract number and SIN, plus a price summary
gsa_rate_stats	"What is the median GSA rate for a project manager?" — the summary only
gsa_vendor_rates	"What rates does this contractor have on its schedule?"

Filters on all three: min_experience / max_experience, education, worksite, business_size, security_clearance, min_rate / max_rate, sort_by / sort_dir.

Auth

None. api.gsa.gov/acquisition/calc/v3 is keyless — no api.data.gov key is needed, unlike gsa-auctions and gsa_perdiem which do use PLATFORM_DATAGOV_KEY.

Data sources

• CALC+ Quick Rate API — https://open.gsa.gov/api/dx-calc-api/
• Endpoint: https://api.gsa.gov/acquisition/calc/v3/api/ceilingrates/
• Rates come from GSA MAS contracts; the figure is the ceiling rate for the current contract year, not a negotiated or paid price.

The older calc.gsa.gov/api/rates/ path found in pre-2026 write-ups is dead (404). calc.gsa.gov now redirects to a landing page on buy.gsa.gov.

Upstream behaviour worth knowing

All measured live on 2026-08-28. The running API differs from its documentation in ways that change answers, so they are listed rather than assumed.

An unrecognised filter value is silently ignored. filter=worksite:Contractor (capital C) and filter=nonsense_field:zzz each return the complete unfiltered result set with HTTP 200 — the same total as sending no filter at all. A caller who asks for contractor-site rates and gets a confident answer may be reading every rate in the schedule. This pack validates every enum and refuses an unknown value rather than forwarding it; the error names the accepted set. A refused call is recoverable, a silently unfiltered benchmark is not.

The vocabularies are case-sensitive in opposite directions, and there are three of them. worksite matches lowercase only (contractor); Contractor is ignored. business_size matches uppercase only (S); s returns zero rows. And the same field is spelled differently depending on where you read it — filter BA, JSON response Bachelors, CSV export small business for filter S. The pack accepts human spellings ("bachelors", "small business", "contractor facility") and maps them.

min_years_experience is an equality filter, not a minimum. Upstream, min_years_experience:5 returns only rows requiring exactly 5 years (667 of 4,396 for "software engineer"). Our min_experience means what a caller means by it — 5 or more — and maps to experience_range:5,99 (2,561 rows, with requirements from 5 to 15+ years).

page and page_size are both ignored. The JSON endpoint returns exactly 20 rows for every query; page=1, page=2 and page=3 return byte-identical rows, and page_size=300 returns 20. export=y returns the complete matching set as CSV instead, so this pack computes percentiles from the export — based_on in every rate_summary states how many rows the numbers came from. The JSON endpoint's own total caps at 10,000 with relation: "gte"; the export count is exact.

Accept: text/csv returns 406. The export responds Content-Type: text/csv, but asking for that type is the one request it refuses. Send */*.

Reading the result

rate_summary is computed over every matching rate, not the rows returned — based_on is the row count behind it and complete is false only if a very broad query hit the pack's byte cap. matched_labor_categories shows which contract titles the keyword actually hit, because labor-category names are free text on the contracts ("Sr. Software Engineer" vs "Software Engineer III") and the spread tells you whether you are benchmarking the right thing.

Quick Start

Add to your MCP client (Claude Desktop, Cursor, Windsurf, etc.):

{
  "mcpServers": {
    "gsa-calc": {
      "url": "https://gateway.pipeworx.io/gsa-calc/mcp"
    }
  }
}

What this endpoint actually serves

tools/list at https://gateway.pipeworx.io/gsa-calc/mcp returns the tools in the table above plus the shared Pipeworx meta-tools — ask_pipeworx, discover_tools, search_within, remember/recall and the rest of the gateway-wide set. So the tool count you see is larger than this table: a single-pack endpoint currently lists roughly 30 shared tools alongside the pack's own. The connection's initialize response states its exact scope, and is the authoritative answer for a given day.

This is deliberate, not multiplexing by accident. The meta-tools are what let a scoped connection answer a question this pack does not cover — via ask_pipeworx, which routes across the whole catalog — without you adding a second MCP server. There is currently no way to mount a pack endpoint without them; if the extra schemas cost you more context than the routing is worth, connect to the full gateway once rather than to several pack endpoints.

Or connect to the full Pipeworx gateway to get every pack's tools listed directly, instead of just this one's:

{
  "mcpServers": {
    "pipeworx": {
      "url": "https://gateway.pipeworx.io/mcp"
    }
  }
}

Both URLs reach the same gateway and the same 1573+ data sources. The only difference is which pack's tools are listed directly; ask_pipeworx reaches all of them from either one.

Standalone (no gateway account)

This package also runs as a local stdio MCP server — no Pipeworx account, no gateway round-trip:

{
  "mcpServers": {
    "gsa-calc": {
      "command": "npx",
      "args": ["-y", "@pipeworx/mcp-gsa-calc"]
    }
  }
}

Or run it directly to confirm it starts:

npx -y @pipeworx/mcp-gsa-calc

It speaks MCP over stdin/stdout and answers initialize/tools/list/tools/call for only this pack's tools — none of the shared meta-tools the gateway connection above adds. Same source, same tools, no ask_pipeworx routing.

Using with ask_pipeworx

Instead of calling tools directly, you can ask questions in plain English — this works on the pack endpoint above as well as on the full gateway:

ask_pipeworx({ question: "your question about Gsa Calc data" })

The gateway picks the right tool and fills the arguments automatically.

More

• Docs and guides
• pipeworx.io

License

MIT