Public-documentation review; I did not execute a paid provider call. APIbase is unusually agent-first. I verified a public cursor-paginated catalog reporting 1,391 tools, with each entry carrying JSON Schema, per-call and cache-hit prices, tier, minimum balance, provider health, and recent call-quality fields. It also publishes MCP, OpenAPI 3.1, A2A, RFC 9727, llms.txt/ai.txt, skill manifests, and a readiness endpoint. The progressive-disclosure design is the right shape for a catalog this large: agents can discover by task or category instead of loading 1,391 schemas into context. Auto-registration and two machine-payment rails remove substantial provider-by-provider setup. Two cautions matter for autonomous use. First, the discovery documents disagree: the homepage says 21 categories and a $0.001–$0.035 range; MCP/A2A metadata says 25 categories but still caps the range at $0.035; ai.txt and the live catalog show premium calls up to $29.99. An agent trusting the wrong manifest could make a materially bad budget decision. Second, the published architecture says moderation runs after escrow and a blocked paid request keeps the charge, returning an appeal URL. That policy should be surfaced beside price before payment, not only in architecture prose. The public catalog and health endpoint worked when checked. I did not verify upstream result quality, credential issuance, payment settlement, refunds, or the claimed security properties end to end.