Washington Code — RCW statutes, WAC agency rules, and bill tracking

Washington state law and legislative activity from the Legislature's own sources, keyless: the Revised Code of Washington (RCW, statutes) by citation, the Washington Administrative Code (WAC, agency rules) by citation, by topic, by structure, by year-end archive, and by rule-making history, and legislative bills — status, amendments and floor votes — by bill number and biennium.

Part of Pipeworx — an MCP gateway connecting AI agents to 1857+ live data sources. This is an independent, unofficial integration — not affiliated with, endorsed by, or published by the upstream provider.

Tools

Citations accept the RCW/WAC prefix, letter-suffixed titles and chapters (296-14A-100, 132C-120-010), and typographic dashes. Bill numbers accept any chamber/version prefix (HB 1000, SHB 1000, 2SHB 1000, bare 1000). Every response carries data_as_of, source and (for RCW/WAC) the exact upstream url.

Related MCP server: minnesota-code

The four capabilities, and which one is only partly there

Miss signals — positive, not inferred

• RCW: a bad citation renders a panel with the id pnlCitationNotFound (HTTP 200). The pack keys on that panel.

• WAC: a nonexistent section answers an HTTP 302 to the chapter's dispositions page (?dispo=true&cite=296-800). The pack fetches with redirect: 'manual' and reads the miss from the status line, returning found:false, reason:"section_not_found" with the dispositions link.

• Anything else that is not a 200 throws a loud error naming the upstream status. A transport failure is never reshaped into found:false (src/index.test.ts pins this — the oklahoma-code lesson, fleet #2742).

• Bills: a nonexistent bill number/biennium combination answers HTTP 200 with an empty array — there is no 404 or error panel for this case. wa_bill_status reads zero records as found:false, reason:"bill_not_found". wa_bill_amendments and wa_bill_votes read an empty list as a normal zero-result answer (a bill can genuinely have no amendments or no recorded roll call), not a miss — the note says so and points at wa_bill_status to confirm the bill itself exists.

Bill tracking (added fleet #3240)

Reads directly from the Washington State Legislature's own bill-tracking web service — not a third-party aggregator (LegiScan/OpenStates already cover all 50 states generically; this is the Legislature's own free data for Washington specifically). Bills are addressed by (biennium, bill number): Washington runs a two-year biennium starting on an odd year ("2025-26"), and bill numbers are reassigned each biennium, so the same number is a different bill two years later. All four tools default to the current biennium when omitted.

wa_session_bills's status filter and what each needs:

wa_session_bills and the bulk Legislature listings it wraps carry no description field — only id, type, chamber and active flag. Call wa_bill_status on a specific bill id for its description and current status.

Archive filenames are fixed-width (measured 2026-10-07)

lawfilesext.leg.wa.gov/law/wacarchive/<year>/htm/… names files with space-padded fields: the numeric title and chapter are right-aligned to 3 characters and padded to 4, the section is appended as typed:

296-800-110  →  WAC 296 -800 -110.htm
1-04-010     →  WAC   1 - 04 -010.htm

2019–2023 nest the file under WAC 296 TITLE/WAC 296 -800 CHAPTER/; 2024 onward is flat under WAC 296 -800 CHAPTER/. The resolver tries the likely layout for the year first and the other second; a 404 at both is section_not_in_archive with the URLs tried, so a one-space error cannot masquerade as "the rule did not exist that year". The tests pin both layouts.

The search index is the Legislature's own, read as its client does

leg.wa.gov/search is a thin client over a SearchUnify instance. Its host, client uid and per-client access token are served to every anonymous visitor inside the client bundle (an.js), so they are configuration we read, not a credential we hold; the pack caches them and re-reads the bundle once if the API rejects them. Requests identify as pipeworx-mcp-washington-code — no Origin or Referer is sent and none is needed (verified 2026-10-07: identical results with and without). cite_prefix filtering is client-side over the top 50 index hits, and the response says so in total_matches_note.

Edge probe (2026-10-07)

Per the standing rule for any new upstream host, every URL shape the WAC tools use was fetched from a throwaway wrangler dev --remote Worker on the prod account before deploy. All answered a Cloudflare Worker exactly as they answer a laptop — no relay needed:

app.leg.wa.gov/WAC/default.aspx?cite=296-800-110         200  117,345 B
app.leg.wa.gov/WAC/default.aspx?cite=296-800-99999       302  → /WAC/default.aspx?dispo=true&cite=296-800
app.leg.wa.gov/WAC/                                      200  144,207 B
app.leg.wa.gov/WAC/default.aspx?cite=296-800             200  187,138 B
app.leg.wa.gov/WAC/registerfiling.aspx?cite=296-800-110  200  109,878 B
lawfilesext…/wacarchive/2020/htm/WAC 296  TITLE/…        200   10,076 B
lawfilesext…/wacarchive/2024/htm/WAC 296 -800  CHAPTER/… 200   10,076 B
lh112524p.searchunify.com/search/searchResultByPost      200   11,313 matches for "safety bulletin board"

Smoke (pre-deploy, 2026-10-07)

smoke.json holds the arguments; all six tools returned non-empty payloads: wa_wac_section 296-800-110 1,386 chars of text + 4-filing history, wa_wac_search "safety bulletin board" 5 of 11,313, wa_wac_browse 296-800 136 sections, wa_wac_archived_section 296-800-110 @2020 1,386 chars, wa_wac_filings 296-800-110 4 WSR filings.

Smoke — bill tracking (pre-deploy, 2026-10-18)

All four bill tools returned non-empty live payloads against the current (2025-26) biennium: wa_bill_status({bill:"HB 1002"}) → status "H Rules 3C", 10 sponsors; wa_bill_amendments({bill:"1002", biennium:"2023-24"}) → 1 amendment, ADOPTED 2023-04-05; wa_bill_votes({bill:"HB 1002"}) → House 3rd Reading vote, 70 yea / 24 nay / 4 excused, 2026-02-10; wa_session_bills({biennium:"2025-26", status:"passed_legislature"}) → 709 bills (397 House / 312 Senate); wa_session_bills({..., status:"signed", agency:"House"}) → 385 bills. The miss case (wa_bill_status({bill:"99999", biennium:"2025-26"})) returned found:false, reason:"bill_not_found" from a genuine empty-array upstream response, not a guess.

Caveats

• RCW and WAC numbers are not contiguous; repealed and recodified sections are normal. wa_wac_browse on the chapter shows what exists today.

• A cite_prefix search that returns zero is a real zero under that prefix in the top 50 hits, not a failure; the note says how many index-wide matches there were.

Data source

Washington State Legislature — app.leg.wa.gov (current RCW and WAC, WSR filings), lawfilesext.leg.wa.gov (annual WAC archive), the Legislature's site-search index, and the Legislature's own legislative bill-tracking data (status, amendments, sponsors, floor votes). Keyless. Washington statutes, agency rules and legislative bill records are public record.

Quick Start

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

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

What this endpoint actually serves

tools/list at https://gateway.pipeworx.io/washington-code/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 1857+ data sources. The only difference is which pack's tools are listed directly; ask_pipeworx reaches all of them from either one.

No MCP client? Call it over HTTP

curl -X POST https://gateway.pipeworx.io/v1/tools/wa_rcw_section \
  -H 'Content-Type: application/json' \
  -d '{"section":"9A.32.030"}'

No account needed for the first calls. Inspect any tool: GET https://gateway.pipeworx.io/v1/tools/wa_rcw_section. Find one: POST https://gateway.pipeworx.io/v1/tools/search_packs with {"query":"..."}.

Run it from npm

@pipeworx/mcp-washington-code is a local stdio bridge to the Pipeworx gateway: your MCP client starts it with npx, and it forwards every call to the same https://gateway.pipeworx.io/washington-code/mcp endpoint shown above. It needs network access; there is no offline mode.

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

Without a key it calls anonymously, capped at 50 calls a day. A free account raises that to 200 a day: get a key at https://pipeworx.io/signup and add "env": { "PIPEWORX_API_KEY": "<your key>" } to the server entry. The key is sent as a Bearer token, the same way a hosted connection sends it, so calls are metered and billed exactly as they are there.

It lists only this pack's tools by default. Set PIPEWORX_META_TOOLS=1 to also list ask_pipeworx and the other gateway-wide tools.

Behind an HTTPS proxy: Node's built-in fetch does not read HTTPS_PROXY by default. Newer Node releases honour it when NODE_USE_ENV_PROXY=1 is set; check your Node version's documentation.

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 Washington Code data" })

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

More

• Docs and guides

• pipeworx.io

License

MIT