MCP server exposing 4 tools for insurance-denials.
This URL is a JSON-RPC 2.0 endpoint over HTTP. Issue POST requests with a JSON-RPC body. Browsers and search crawlers land here on GET.
POST https://gateway.pipeworx.io/insurance-denials/mcp
Content-Type: application/json
{"jsonrpc":"2.0","id":1,"method":"tools/list"}insurer_denial_rates — Which health insurers deny the most claims — US marketplace issuers ranked by the share of in-network claims they denied, for plan year 2026. Answers "what percentage of claims does my insurance company deny", "which insurer denies the most", "how often does <company> deny claims", and comparisons between insurers in a state. Returns each issuer with claims received, claims denied, the denial rate as a percentage, and how many marketplace plans it offers. Filter by state (two-letter code) or by market — medical plans (Individual QHP), standalone dental (Individual SADP, which denies at much higher rates than medical), or small-group SHOP; the market filter selects which ISSUERS to include, since CMS publishes these counts per issuer rather than per market. Sourced from the CMS Transparency in Coverage Public Use File, which insurers report into under federal rule; covers HealthCare.gov states only, so issuers on state-run exchanges such as California and New York are not present.insurer_appeal_outcomes — Does appealing a denied health-insurance claim work? Marketplace issuers ranked by the share of appeals that were OVERTURNED in the patient's favour, plan year 2026. Answers "is it worth appealing a denied claim", "what percentage of insurance appeals succeed", "how often does <company> reverse a denial", and which insurer most often changes its mind. Returns internal appeals (decided by the insurer itself) and external appeals (decided by an independent reviewer) separately, with how many were filed, how many were overturned, and the overturn percentage — the two differ a lot and the external number is the independent one. Sourced from the CMS Transparency in Coverage Public Use File; covers HealthCare.gov states only, so state-run exchanges such as California and New York are not present.insurer_denial_profile — Everything reported for ONE named health insurer: claims received and denied in and out of network, the denial rate, and both internal and external appeal outcomes, for plan year 2026. Use when a caller names a company — "how often does Ambetter deny claims", "Blue Cross denial rate in Texas", "what happens if I appeal with Oscar". Matches on the insurer's name and is forgiving about punctuation, case and partial names; an issuer selling in several states returns one entry per state, since CMS reports these figures per issuer per state. Sourced from the CMS Transparency in Coverage Public Use File; covers HealthCare.gov states only.insurer_denial_coverage — What this data covers before you rely on it: the plan year, how many issuers and states are present, which states are included, and the counts of issuers whose denial or appeal figures CMS suppressed. Use to check whether a state or insurer is in scope at all, and to tell "we hold no data for this state" apart from "this state's insurers deny nothing" — the CMS Transparency in Coverage file covers HealthCare.gov states only.Code samples (curl / TypeScript / one-click client install), schemas, and the live playground are on the pack page:
https://pipeworx.io/packs/insurance-denials/
Pipeworx is an open MCP gateway connecting AI agents to live data. pipeworx.io