Verity MCP Server

Instructions

Implementation Reference

• src/index.ts:380-394 (handler)

  Handler function that fetches the specific policy from Verity API endpoint `/policies/{policy_id}` using the shared verityRequest helper, formats the result with formatPolicy, and returns it as text content. Handles errors gracefully.
  async ({ policy_id, include }) => { try { const result = await verityRequest<any>(`/policies/${encodeURIComponent(policy_id)}`, { params: { include }, }); return { content: [{ type: "text", text: formatPolicy(result.data, true) }], }; } catch (error) { return { content: [{ type: "text", text: `Error getting policy: ${error instanceof Error ? error.message : String(error)}` }], }; } }
• src/index.ts:375-378 (schema)

  Zod input schema validating the required policy_id string and optional include string for additional data fields.
  inputSchema: { policy_id: z.string().min(1).describe("Policy ID (e.g., L33831, A52458, NCD220.6)"), include: z.string().optional().describe("Additional data: 'criteria', 'codes', 'attachments', 'versions'"), },
• src/index.ts:365-395 (registration)

  Registration of the 'get_policy' tool on the MCP server, including description, input schema, and handler function reference.
  server.registerTool( "get_policy", { description: `Get detailed information about a specific Medicare coverage policy. Use this after finding a policy ID from search_policies or lookup_code. Can include criteria, codes, attachments, and version history. Examples: - get_policy("L33831") - LCD for ultrasound guidance - get_policy("A52458", { include: "criteria,codes" }) - with coverage criteria`, inputSchema: { policy_id: z.string().min(1).describe("Policy ID (e.g., L33831, A52458, NCD220.6)"), include: z.string().optional().describe("Additional data: 'criteria', 'codes', 'attachments', 'versions'"), }, }, async ({ policy_id, include }) => { try { const result = await verityRequest<any>(`/policies/${encodeURIComponent(policy_id)}`, { params: { include }, }); return { content: [{ type: "text", text: formatPolicy(result.data, true) }], }; } catch (error) { return { content: [{ type: "text", text: `Error getting policy: ${error instanceof Error ? error.message : String(error)}` }], }; } } );
• src/index.ts:107-163 (helper)

  Helper function formatPolicy used by the handler to generate a human-readable string representation of policy data, including title, status, sections, criteria, and codes.
  function formatPolicy(policy: any, detailed = false): string { const lines: string[] = []; lines.push(`Policy: ${policy.policy_id} - ${policy.title}`); lines.push(`Type: ${policy.policy_type} | Status: ${policy.status}`); if (policy.jurisdiction) lines.push(`Jurisdiction: ${policy.jurisdiction}`); if (policy.effective_date) lines.push(`Effective: ${policy.effective_date}`); if (policy.retire_date) lines.push(`Retired: ${policy.retire_date}`); if (detailed) { if (policy.description) lines.push(`\nDescription: ${policy.description}`); if (policy.summary) lines.push(`\nSummary: ${policy.summary}`); if (policy.mac) { lines.push(`\nMAC: ${policy.mac.name} (${policy.mac.jurisdiction_name})`); if (policy.mac.states) lines.push(`States: ${policy.mac.states.join(", ")}`); } if (policy.sections) { if (policy.sections.indications) { lines.push(`\n--- Indications ---\n${policy.sections.indications.slice(0, 1000)}${policy.sections.indications.length > 1000 ? "..." : ""}`); } if (policy.sections.limitations) { lines.push(`\n--- Limitations ---\n${policy.sections.limitations.slice(0, 1000)}${policy.sections.limitations.length > 1000 ? "..." : ""}`); } if (policy.sections.documentation) { lines.push(`\n--- Documentation Requirements ---\n${policy.sections.documentation.slice(0, 1000)}${policy.sections.documentation.length > 1000 ? "..." : ""}`); } } if (policy.criteria && Object.keys(policy.criteria).length > 0) { lines.push("\n--- Coverage Criteria ---"); Object.entries(policy.criteria).forEach(([section, blocks]: [string, any]) => { lines.push(`\n[${section.toUpperCase()}]`); blocks.slice(0, 3).forEach((block: any) => { lines.push(` - ${block.text.slice(0, 200)}${block.text.length > 200 ? "..." : ""}`); if (block.tags?.length) lines.push(` Tags: ${block.tags.join(", ")}`); }); if (blocks.length > 3) lines.push(` ... and ${blocks.length - 3} more criteria`); }); } if (policy.codes && Object.keys(policy.codes).length > 0) { lines.push("\n--- Associated Codes ---"); Object.entries(policy.codes).forEach(([system, codes]: [string, any]) => { lines.push(`\n[${system}] (${codes.length} codes)`); codes.slice(0, 10).forEach((c: any) => { lines.push(` - ${c.code}: ${c.display || "No description"} [${c.disposition}]`); }); if (codes.length > 10) lines.push(` ... and ${codes.length - 10} more codes`); }); } } if (policy.source_url) lines.push(`\nSource: ${policy.source_url}`); return lines.join("\n"); }
• src/index.ts:25-66 (helper)

  Shared helper function verityRequest for making authenticated API calls to the Verity service, used by all tools including get_policy.
  async function verityRequest<T>( endpoint: string, options: { method?: "GET" | "POST"; params?: Record<string, string | number | boolean | undefined>; body?: unknown; } = {} ): Promise<T> { const { method = "GET", params, body } = options; // Build URL with query params const url = new URL(`${VERITY_API_BASE}${endpoint}`); if (params) { Object.entries(params).forEach(([key, value]) => { if (value !== undefined && value !== null && value !== "") { url.searchParams.append(key, String(value)); } }); } const headers: Record<string, string> = { Authorization: `Bearer ${VERITY_API_KEY}`, "Content-Type": "application/json", Accept: "application/json", }; const response = await fetch(url.toString(), { method, headers, body: body ? JSON.stringify(body) : undefined, }); const data = await response.json(); if (!response.ok) { const errorMsg = data.error?.message || `API error: ${response.status}`; const hint = data.error?.hint || ""; throw new Error(hint ? `${errorMsg}. Hint: ${hint}` : errorMsg); } return data as T; }