Gemini Exchange API vs HTX trading 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.

HTX trading API 25

The editorial half. A closed service whose user agreement exists but couldn't be read (script-drawn pages), so the licence clarity is unknown rather than unclear (10 of 30). The privacy policy was not read (0 of 30, unchecked). The testnet shutdown and the 2022 changelog entries are dated, with no deprecation policy (5 of 20). No subprocessor or data-location statement read (0 of 20). 10 + 0 + 5 + 0 = 15.

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.

HTX trading API 40

No OpenAPI or other machine-readable contract found in the docs or the GitHub accounts (0). No llms.txt on htx.com, and the readable reference is a static page (0). Each endpoint states its purpose and parameters, without when-to-use guidance (12 of 20). Parameter tables carry types, required flags and enums for order types and states (10 of 15). Request and response examples throughout and error-code tables with messages (11 of 15). Versions v1 and v2 are mixed in one reference whose last changelog entry is 24 June 2022, while HTX's newer docs on htx.com couldn't be read (7 of 15). 0 + 0 + 12 + 10 + 11 + 7 = 40.

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.

HTX trading API 38

Read with the hosted lines. No status page found; status.htx.com does not resolve and nothing on htx.com was readable (0). No readable incident history (5). Rate limits documented per endpoint with numbers, 100 order calls per 2 seconds per UID and so on, with remaining-quota headers (15). No 429 or Retry-After behaviour is documented and the only limit error named is 1006 for conditional orders; a client-order-id unique within 8 hours and an idempotent withdrawal id give safe retries on writes (8 of 15). No SLA found (0). The spot and swap APIs are generally available (10). 0 + 5 + 15 + 8 + 0 + 10 = 38.

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.

HTX trading API 57

Read as a closed service. The readable changelog ends on 24 June 2022, but the official contract SDKs were pushed on 21 October 2026 and the spot SDKs in April and July 2026, so the API surface is still being maintained; judgement call (20 of 30). SDK pushes on 30 July, 23 August and 21 October 2026 are commits, not releases (10 of 20). A Telegram group for API support and a support centre, neither tested; GitHub issues not read (8 of 15). Official SDKs in five languages (15). No CI seen, dependencies not checked (4 of 10). 20 + 10 + 8 + 15 + 4 = 57.

Gemini Exchange API 78

Revocable API keys with one role each (Trader, Fund Manager, Auditor, Administrator), HMAC-SHA384 signing with a nonce, and OAuth 2.0 with scopes, PKCE S256, single-use refresh tokens and RFC 7009 revocation; no IP allow-list documented and no key expiry (28 of 30). Auditor is read-only, a Trader key cannot withdraw, approved withdrawal addresses are a Fund Manager action, and the MCP server refuses funds-moving tools without confirm: true (18 of 20). The MCP server wraps every response in untrusted-output markers, strips control and bidi characters and redacts memos, labels and agreement text; the REST docs say nothing on the subject (13 of 15). Order and transfer history are readable, but no per-key audit log or API access log was found (5 of 15). security.txt with a PGP contact and a bug bounty paying $150 to $20,000, scoped to the sandbox hosts; no certification was read and no public advisory process was found (14 of 20). 28 + 18 + 13 + 5 + 14 = 78.

HTX trading API 51

HMAC-signed keys with Read, Trade and Withdraw permissions, sub-user keys without Withdraw, up to 20 bound IPs, revocation in the account and a 90-day expiry without IP binding. The AccessKeyId and the HMAC signature travel as query parameters; the secret does not, so no deduction for a secret in the URL (24 of 30). Read-only keys and withdraw-free keys exist; no server-side confirmation for orders or withdrawals (14 of 20). The API returns the exchange's own data, no untrusted content (10). No per-call log or key-use history found for the operator (3 of 15). No security.txt, disclosure policy or certification found on the pages that loaded (0 of 20). 24 + 14 + 10 + 3 + 0 = 51.

Gemini Exchange API 40

No machine payment protocol (0). The API fee schedule is public per tier without login, 0.6% maker and 1.2% taker at the base tier (20). The API is free to call, public market data needs no key, and the sandbox credits test funds with no card (20). A person must sign up in a browser with identity checks, mint a key or approve an OAuth grant, and production OAuth apps wait for Gemini's review (0). 0 + 20 + 20 + 0 = 40.

HTX trading API 15

No machine payment protocol (0). The fee schedule at htx.com/fee is drawn by script and answered no text, so no price is recorded first-hand (0 of 20, unchecked). Public market data needs no key, card or account; trading needs a verified and funded account. Judgement call (15 of 20). A person must sign up in a browser and pass identity checks (0). 0 + 0 + 15 + 0 = 15.