MCP QUEEN
io.github.Invaro/opentax A
Verifiable US tax oracle for AI agents: cited, machine-checkable federal and state tax computation
AI & Agentsv0.2.1streamable-httpopentax.invaro.ai
Grade evidence — probed 2026-07-23 16:16 UTC
| Criterion | Points | Observed |
|---|---|---|
| reachability | 25 / 25 | HTTP 200, initialize accepted in 436ms |
| protocol | 15 / 15 | valid JSON-RPC initialize result, protocolVersion 2025-06-18, serverInfo opentax@0.1.0 |
| tooling | 35 / 35 | tools/list OK: 15 tools e.g. "calculate_tax"; 15/15 described, 15/15 fully-typed schemas, median description 320 chars |
| latency | 10 / 10 | initialize round-trip 436ms |
| provenance | 5 / 15 | description present; no repository URL; version 0.2.1; namespace io.github.Invaro does NOT match remote host (expected *.invaro.github.io) |
Score 90/100 · latency 436ms · 15 tools · protocol access: open ⓘ
Trust receipt
Security, data integrity, citation quality, and advertised claims are measured separately from protocol uptime. Missing evidence is marked unverified, never converted into a pass.
| Dimension | Metric | Status | Evidence | Source |
|---|---|---|---|---|
| citation_quality | citation_capability_advertised | unverified | Metadata/tool descriptions advertise citation or evidence capability: Verifiable US tax oracle for AI agents: cited, machine-checkable federal and state tax computation calculate_tax Compute US federal INDIVIDUAL income tax (or balance due if withholding is given) from a con | tent-addressed corpus of cited rules | own keys are rejected, calculate_business_tax Compute US federal BUSINESS-ENTITY tax from the same cited corpus: check-the-box entity classification, Form 1120 corporate income tax (§ 179/168(k)/174A/163(j)/DRD/NOL, § 250, GBC/FTC/BEAT), S-corp entity taxes, corpo. No response-level citation benchmark has verified this claim yet. | live_probe |
| security | authentication_boundary | observed | Live protocol probe observed auth_state=open. This describes discovery/access behavior; it is not by itself a vulnerability finding. Observed value: open | live_probe |
Machine-readable receipt: /api/trust/io.github.Invaro/opentax.json
Connect your agent
Claude Code:
claude mcp add --transport http opentax https://opentax.invaro.ai/mcp
Generic MCP client config:
{ "mcpServers": { "opentax": { "type": "http", "url": "https://opentax.invaro.ai/mcp" } } }
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Share this server: permalink https://mcpqueen.com/s/io.github.Invaro/opentax · referral link https://mcpqueen.com/go/io.github.Invaro/opentax (counts as “routed via the queen”).
Own this server? Embed your grade badge
Live operational-grade badge, re-probed continuously — not a security or data-quality certification. Put it in your README and link to the complete receipt:
[](https://mcpqueen.com/s/io.github.Invaro/opentax)
Think the grade is wrong? Fix the finding the evidence shows, then the next probe cycle picks it up automatically (full cycle ≈ 3 days) — or open a dispute via the MCP endpoint.
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Probe history
| When (UTC) | Grade | Score | Latency |
|---|---|---|---|
| 2026-07-23 16:16 | A | 90 | 436ms |