Build compliance into your product, not a portal.
Every Plain Dot product — Tax filing, Check verification, and Excise, ADA, and Extension as they launch — is reachable through one authenticated API and a hosted MCP server. This is how enterprises use Plain Dot as infrastructure: one integration instead of a different vendor for every compliance domain.
What this replaces
- A patchwork of vendor-specific SDKs for tax and verification
- A separate API integration per compliance domain (filing, verification, excise, accessibility)
- Screen-scraping or manual portal work to move data
- Building your own IRS IRIS or TIN matching integration in-house
What's inside
One integration instead of five vendor contracts
Enterprises that need tax filing, verification, and adjacent compliance today typically integrate a different vendor's API for each domain. Plain Dot | API collapses that into one authentication model, one usage dashboard, and one commercial relationship — across every Plain Dot product, present and future.
- Single API key works across Tax, Check, and every product as it ships
- One usage and billing dashboard instead of per-vendor invoices
- New products (Excise, ADA, Extension) appear as new endpoints, not new integrations
Every Plain Dot product, one API surface
TIN matching, W-9 requests, form generation, IRS submission, and status tracking are all reachable from the same authenticated API.
- REST endpoints with predictable, versioned schemas
- Idempotency keys on every write
- Sandbox environment mirrors production
A hosted MCP server for agentic workflows
Give an AI agent scoped access to file a 1099, check a TIN, or pull filing status — without giving it your dashboard credentials.
- Hosted MCP server, no self-hosting required
- Scoped API keys per integration
- Same audit trail as dashboard-driven actions
Usage, logs, and webhooks built for production
Track usage per key, inspect request logs, and subscribe to webhooks for filing status, TIN match results, and corrections.
- Per-key usage and rate-limit visibility
- Searchable request logs
- Webhook delivery with retries
How it works
Why teams switch
Enterprises building compliance into their own product usually end up integrating a separate API for filing, a separate one for verification, and a separate one for anything adjacent. Plain Dot | API is built to replace that pattern:
API coverage
Every product — Tax, Check, and more
Partial coverage, portal-first vendors
Multi-domain coverage
One API across filing, verification, and adjacent compliance
A different vendor API per compliance domain
Agent access
Hosted MCP server included
Not offered, or requires self-hosting
Idempotency
Built into every write endpoint
Varies by vendor, often undocumented
Sandbox parity
Mirrors production schemas
Limited or stubbed sandbox
Results
for every product
Tax filing and Check verification share one authentication and usage model.
portal-only actions
Anything doable in the dashboard is doable through the API or MCP server.
Frequently asked
Compliance rails for whatever you're building.
REST endpoints and a hosted MCP server for every Plain Dot product.