Gemini Exchange API vs Kraken API

Gemini Exchange API 75

The editorial half. A closed service under a user agreement that names its entities by state, with the MCP server and SDKs open under Apache-2.0 (18 of 30). The privacy policy of 11 May 2026 names entities and processing countries, ties retention to need without numbers and names provider categories only, with no DPA or subprocessor list found (16 of 30). The revision history records removals and type changes with dates, but the upcoming-changes page is "TBD" and no notice period is stated (8 of 20). Processing countries are named (US, Ireland, UK, Malta, Singapore, Australia) and providers by category, with no named subprocessors (12 of 20). 18 + 16 + 8 + 12 = 54.

Kraken API 65

The editorial half. A closed service with clear terms naming regional Payward entities under California law; the CLI is MIT (15 of 30). The privacy notice was not read (5 of 30). The changelog dates deprecations and the terms carry a last-updated date (16 of 20). No subprocessor or data-location statement read (0 of 20). 15 + 5 + 16 + 0 = 36.

Gemini Exchange API 88

OpenAPI 3 for REST (specs/openapi/rest.yaml), AsyncAPI for WebSocket, a prediction-markets OpenAPI file and a specs/index.json catalogue; the MCP server's tools take zod schemas published as JSON Schema (25). llms.txt, llms-full.txt, agents.md, an agent card and an agent skills index (10). Endpoint pages state purpose, the Build an agent guide says what to establish before acting and when to stop, and MCP tool descriptions tell the model when to confirm; the docs don't say when not to use an endpoint (15 of 20). Typed inputs with enums for order types, options and sessions, required fields marked, decimals as strings since 7 July 2026 (12 of 15). Examples throughout, samples in three languages, and an error-codes page with 53 named reasons and their HTTP statuses (14 of 15). A revision history dated from 2015 to 28 October 2026 and versioned paths (v1, v2), but the upcoming-changes page reads "TBD" (12 of 15). 25 + 10 + 15 + 12 + 14 + 12 = 88.

Kraken API 80

No OpenAPI file was found for the REST API in the docs read; the CLI's agents/tool-catalog.json gives JSON Schema inputs for all 188 commands and the 152 MCP tools (15 of 25). The docs serve Markdown twins such as quickstart.md and the CLI ships llms.txt, AGENTS.md and CONTEXT.md (10). Endpoint pages and guides on order lifecycle, errors and rate limits say what each call does, with less on when not to use one (15 of 20). Enums for order types, time in force and flags, and enums and required fields in the tool catalogue (12 of 15). Python, Node.js and cURL examples, an errors guide and the CLI's error-catalog.json with retry guidance (13 of 15). A changelog of 120 dated entries with deprecations dated (15). 15 + 10 + 15 + 12 + 13 + 15 = 80.

Gemini Exchange API 88

Read as a closed hosted service with an open repository. The revision history's latest entry is 28 October 2026 and the repository was pushed on 5 October (30). Thirteen dated entries between 2 September and 28 October 2026 (20). The nine open items on the repository are all pull requests with replies, Dependabot included, and the docs name trading@gemini.com for developer support; no public issue tracker was tested (15 of 25). Not in the official MCP registry, but current official SDKs, TypeScript 0.1.1 of 23 September and Go 0.1.0 of 29 August 2026 (15). CI workflows validate and publish both SDKs and the MCP server has tests; dependencies are current (8 of 10). 30 + 20 + 15 + 15 + 8 = 88.

Kraken API 81

Read as a closed service with an open-source client. Changelog entry of 27 October 2026 and kraken-cli v0.5.1 on 29 October (30). Fourteen changelog entries since 19 August 2026 and CLI tags on 6 and 7 August and 28 and 29 October (20). A public changelog, api@kraken.com, a status page and a CLI repository merging pull requests at the end of October; issue replies not read (11 of 15). An official Rust SDK pushed in October 2026 and a Go module from January; the MCP server is not in the official registry (12 of 15). The CLI has release and secure SDLC workflows, deny.toml and a pinned toolchain; the SDK's CI not read (8 of 10). 30 + 20 + 11 + 12 + 8 = 81.

Gemini Exchange API 73

Read with the hosted lines on the REST API at api.gemini.com. status.gemini.com is a Statuspage site with component history (20). Its Atom feed for 10 September to 3 November 2026 holds 25 entries, mostly scheduled trading and FIX upgrades of 15 to 60 minutes with possible order timeouts, single-network deposit delays, and incorrect perpetual index prices for about 3.5 hours on 15 and 16 October; a 3-hour scheduled eOTC window was planned and outside the core API. Minor only (20). Rate limits with numbers, 120 a minute public and 600 private plus per-endpoint limits (15). 429 is documented but with no Retry-After or backoff guidance, and client order ids are recommended without duplicate rejection, so retries are not safe by contract; the heartbeat cancel is a safety net rather than idempotency (8 of 15). No SLA found (0). Generally available (10). 20 + 20 + 15 + 8 + 0 + 10 = 73.

Kraken API 67

Read with the hosted lines on the spot API. status.kraken.com is a Statuspage site with REST, WebSocket and FIX components (20). The incidents feed read covers 4 September to 3 November 2026. On 30 October spot and derivatives clients could not connect or submit orders across web, mobile, REST, WebSocket and FIX for 59 minutes 39 seconds, rated minor by Kraken; on 28 October some FIX clients were rejected on reconnection for 1 hour 59 minutes while other interfaces worked; the futures engine was degraded for 3 minutes on 13 October. A whole-exchange order outage 21 seconds short of an hour is read as one major (10 of 30). Numeric limits per key by tier and per pair for the matching engine (15). EAPI:Rate limit exceeded and EService:Throttled with a retry timestamp, a client order id and a validate flag on orders, but no Retry-After header (12 of 15). No SLA (0). Generally available (10). 20 + 10 + 15 + 12 + 0 + 10 = 67.