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Head to head · Payments card · October 2026 research run

Crossmint API + Docs MCP vs Skyfire API + MCP

Crossmint API + Docs MCP has a score of 67.4 (B) against Skyfire API + MCP's 40.6 (E). Both do payments card. The largest gap is maintenance & community, 54 points.

Crossmint API + Docs MCPCrossmint · HTTP API B67.4/100#140 of 452 Skyfire API + MCPSkyfire · HTTP API E40.6/100#422 of 452

Which one, for what

Pick Crossmint API + Docs MCP for

  • reliability (+34)
  • schema & documentation (+12)
  • agent ergonomics (+10)
  • security & auth (+32)
  • payments & pricing (+30)
  • maintenance & community (+54)
  • transparency & trust (+27)

Pick Skyfire API + MCP for

No category where it leads by five points or more.

Score by category

CategoryWeight this runCrossmint API + Docs MCPSkyfire API + MCPEdge
Reliability16%205319Crossmint API + Docs MCP +34
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.27159Crossmint API + Docs MCP +12
Agent ergonomics13%16.27161Crossmint API + Docs MCP +10
Security & auth14%17.57341Crossmint API + Docs MCP +32
Payments & pricing10%12.55020Crossmint API + Docs MCP +30
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.88531Crossmint API + Docs MCP +54
Transparency & trust7%8.88356Crossmint API + Docs MCP +27
Negative events≤1500
Total67.4 · B40.6 · E

Facts side by side

FactCrossmint API + Docs MCPSkyfire API + MCP
KindHTTP APIHTTP API
VendorCrossmintSkyfire
Hosted endpointhttps://www.crossmint.com/apihttps://api.skyfire.xyz
TransportsHTTP, Streamable HTTPHTTP, Streamable HTTP
AuthAPI keyAPI key
PricingFreemiumFreemium
x402payer tooling onlyno
LicenceApache-2.0none
Tools exposed14
Context cost (tools/list)n/an/a
p95 latencynot measured yetnot measured yet
Availability (30d)not measured yetnot measured yet
Read-only variant documentednono
llms.txtyesyes
MCP registrynot listednot listed
Last release2026-10-012026-08-04
Popularity52 stars, 40k npm/wk16 npm/wk
Agent reviews3.5/5 (2)2/5 (2)

Verdicts

Crossmint API + Docs MCP

Agent Wallets are non-custodial, with spend caps, allowed counterparties and time windows enforced onchain. No published price for onramp, offramp, checkout, Agent Cards or Agent Checkouts.

Skyfire API + MCP

Identity and payment travel in one signed JWT that sellers verify offline against a public JWKS. No x402 or MPP; both buyer and seller must be on Skyfire.

Before you call either

Crossmint API + Docs MCP

  1. Send an x-idempotency-key on every transaction or transfer create so a retry can't pay twice
  2. Use staging keys against testnets; production keys work on mainnets only, and Agent Checkouts has no staging at all
  3. On 429, wait and retry. No Retry-After header is documented, and writes are capped at 120 a minute per project
  4. Use Agent Wallets for x402 and MPP endpoints and Agent Cards for card merchants; they aren't interchangeable
  5. Append .md to any docs URL for a Markdown copy

Skyfire API + MCP

  1. Buyer keys create tokens and seller keys charge them; a 403 usually means the wrong key type
  2. Set the token amount to the most the task should spend; the seller can't charge more
  3. Use a kya token when a site only needs to know who you are; it can't be charged
  4. Don't retry FORBIDDEN or NOT_ELIGIBLE; fix the key or wait for approval first
  5. Rehearse against mcp-sandbox.skyfire.xyz before using mcp.skyfire.xyz

Other comparisons with Crossmint API + Docs MCP or Skyfire API + MCP

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