MCP Server Pricing
Two tiers — a permanent anonymous free tier for open experimentation, and a Bearer pilot tier for production workloads that need higher rate limits and a direct support channel. The free tier will always be free. Bearer pilots are handled by email so we can scope the work together before anything gets metered.
Two tiers
Both tiers hit the same endpoint (https://mcp.digitalcalculator.info/mcp) and share the same 13 calculator tools with identical calculation math. The anonymous-parity invariant (per our versioning contract) guarantees that anonymous and authenticated responses are byte-identical for the same inputs — the only difference is what the surrounding infrastructure lets you do at scale.
Anonymous tier — Always Free
The default tier. No signup, no API key, no email address. Just POST to the endpoint and it works.
- 13 MCP tools — mortgage, loan, compound interest, savings, inflation, 401(k), Social Security, paycheck, IRA, Roth conversion, RMD, HSA, emergency fund
- Penny-exact math — every response is byte-parity with the corresponding calculator on digitalcalculator.info (parity-tested via Vitest)
- Full response envelope — YMYL disclaimer, methodology URL + version, engine version, calculation timestamp on every call
- Rate limit — API Gateway global throttle of 100 requests/min across all anonymous callers (burst 50). This is a shared bucket; heavy sustained load from one caller can degrade the experience for others
- Support — the FAQ, the API Reference, and the general admin@markcolabs.com inbox (best-effort, community-style response)
- Terms — governed by the hosted-API terms in
LICENSE-API.md(acceptable use, no warranty)
The anonymous tier is the right choice for exploration, prototypes, individual developers, hobby agents, and any workload where "healthy for everyone" throttling is acceptable. It is not going away.
Bearer tier — Contact for pilot
Bearer is for production integrations where the anonymous tier's shared throttle is the wrong shape — typically a fintech app with steady daily volume, a research team running batched simulations, or a B2B integration where per-key metering and a support channel matter more than "no signup."
What Bearer buys today, committed:
- Higher rate limits — a dedicated per-key sliding window separate from the anonymous global bucket, sized to the pilot use case (see the contract for the framework)
- Direct support — email channel with the maintainer, priority triage for issues that affect your integration
- Usage attribution — per-key call counts for your billing reconciliation and compliance audit needs
- Contract-backed contract — a real relationship covered by the versioning contract (published semver policy, deprecation windows, anonymous-parity invariant)
Pricing is scoped per pilot — volume, support level, and pilot length drive it. We don't publish a rate card yet because we haven't run enough pilots to know what the right numbers are, and we'd rather have that conversation together than guess wrong in public. Contact us to talk it through.
Feature comparison
| Feature | Anonymous (Free) | Bearer (Pilot) |
|---|---|---|
| All 13 calculator tools | Yes | Yes |
| Byte-parity math (penny-exact vs. site) | Yes | Yes (invariant — never differs) |
| Rate limit shape | Shared global throttle (100 req/min, burst 50) | Dedicated per-key window, sized to pilot |
| Per-caller identity + usage attribution | No | Yes (per-key call counts) |
| Support channel | Best-effort general inbox | Direct maintainer email, priority triage |
| Terms governing the endpoint | LICENSE-API.md |
LICENSE-API.md + pilot agreement |
| Versioning contract coverage | Yes (see the contract) | Yes (same contract; anonymous-parity invariant guarantees no divergence) |
| Onboarding | None — just call the endpoint | Email → pilot scoping → issued key (see onboarding) |
What Bearer does NOT buy (yet)
We are honest about the current committed benefits above. Formal SLAs, an uptime dashboard, and a self-serve customer portal are on the roadmap but not shipped — if any of those matter for your integration, tell us during the pilot conversation so we can weigh them against other work.
The contract
Both tiers are covered by the same versioning contract published at /mcp/contract/. That page defines the SemVer policy (what a major, minor, or patch bump means for the tool surface), the deprecation window for anything we change, and the anonymous-parity invariant — the promise that authenticated and anonymous callers receive byte-identical responses to the same inputs. Read that page before starting a pilot so you know exactly what the change surface looks like.
Get in touch
Ready to talk about a Bearer pilot? Email admin@markcolabs.com with a short description of:
- What you're building (one paragraph)
- Which tools you'd be calling and roughly how often
- What "success" looks like for the pilot
- Any timing constraint (production launch date, procurement window, etc.)
We reply within two business days and schedule a scoping call from there. If a pilot doesn't make sense yet — for example, if the anonymous tier is genuinely sufficient for your use case — we will tell you that too.
General questions that aren't pilot-related still go to admin@markcolabs.com.
References
- MCP Server overview — what the server is + how to connect
- Quickstart — first call in under 5 minutes (anonymous tier)
- API Reference — all 13 tools with input schemas and output shapes
- Versioning contract — SemVer policy, deprecation window, anonymous-parity invariant
- Bearer pilot onboarding — how a pilot is scoped, issued, and reviewed
- FAQ — accuracy, YMYL posture, support