# GPT55 Model Gateway API

**Canonical:** https://apis.io/apis/558686-xyz/gpt55-model-gateway-api/  
**Provider:** gpt55-token-gateway — https://apis.io/providers/558686-xyz/  
**Base URL:** https://gpt55.558686.xyz  
**Documentation:** https://gpt55.558686.xyz/x402/service

GPT55 Model Gateway API is one of 5 APIs that [gpt55-token-gateway](https://apis.io/providers/558686-xyz/) publishes on the [APIs.io](https://apis.io/) network, described by a machine-readable OpenAPI specification. Tagged areas include x402, AI Gateway, OpenAI-Compatible, LLM, and USDC. The published artifact set on APIs.io includes an OpenAPI specification, API documentation, an API reference, a getting-started guide, pricing, and rate-limit docs.

OpenAI-compatible, x402-paid model gateway at https://gpt55.558686.xyz. The provider's own OpenAPI 3.1.0 document declares 37 operations on servers[] https://gpt55.558686.xyz, every one with a unique operationId and a summary: GET /v1/models (answers 200 anonymously with seven model ids and per-model pricing), POST /v1/chat/completions plus model-specific routes (/standard, /gpt-5.6-sol, /gpt-5.6-luna, /gpt-5.6-terra, /gpt-5.6, /gpt-5.5, /gpt-5.3-codex, /metered), GET quote routes for 100-call prepaid packs, POST text tools (translate in three tiers, summarize, rewrite, answer, code-review, extract-json), three Sub2API billing helpers, and retained deterministic tools (timestamp, query-parse, EVM wallet balance, x402 MCP integration kit, x402 Bazaar search, wallet signing safety pack). Every paid operation documents a 200 and a 402; an unpaid request returns the x402 v2 quote (PAYMENT-REQUIRED header + JSON accepts[]) and the same request is retried with X-PAYMENT. Prices are carried in x-x402-price / x-gpt55-product on each operation; the spec declares no securitySchemes and no components.schemas.

## Operations (37)

| Method | Path | Summary |
|---|---|---|
| GET | `/v1/models` | models |
| POST | `/v1/chat/completions` | completions |
| POST | `/v1/chat/completions/standard` | GPT-5.6 Luna Standard chat completion |
| POST | `/v1/chat/completions/gpt-5.6-sol` | GPT-5.6 Soul chat completion |
| POST | `/v1/chat/completions/gpt-5.6-luna` | GPT-5.6 Luna chat completion |
| POST | `/v1/chat/completions/gpt-5.6-terra` | GPT-5.6 Terra chat completion |
| POST | `/v1/chat/completions/gpt-5.6` | GPT-5.6 Soul chat completion alias |
| POST | `/v1/chat/completions/gpt-5.5` | gpt-5.5 |
| POST | `/v1/chat/completions/gpt-5.3-codex` | gpt-5.3-codex |
| POST | `/v1/chat/completions/metered` | metered |
| GET | `/v1/paid/call-packs/gpt-5.6-sol-100` | gpt 5.6 sol 100 |
| GET | `/v1/paid/call-packs/gpt-5.6-luna-100` | gpt 5.6 luna 100 |
| GET | `/v1/paid/call-packs/gpt-5.6-terra-100` | gpt 5.6 terra 100 |
| GET | `/v1/paid/call-packs/gpt-5.5-100` | gpt 5.5 100 |
| GET | `/v1/paid/call-packs/gpt-5.3-codex-100` | gpt 5.3 codex 100 |
| POST | `/v1/tools/translate` | translate |
| POST | `/v1/tools/translate/standard` | standard |
| POST | `/v1/tools/translate/plus` | plus |
| POST | `/v1/tools/translate/professional` | professional |
| POST | `/v1/tools/summarize` | summarize |
| POST | `/v1/tools/rewrite` | rewrite |
| POST | `/v1/tools/answer` | answer |
| POST | `/v1/tools/code-review` | code review |
| POST | `/v1/tools/extract-json` | extract json |
| POST | `/v1/tools/sub2api-official-metered-invoice` | sub2api official metered invoice |
| POST | `/v1/tools/sub2api-balance-ledger-simulator` | sub2api balance ledger simulator |
| POST | `/v1/tools/gpt55-plus-half-price-subscription` | gpt55 plus half price subscription |
| GET | `/v1/tools/timestamp` | timestamp |
| GET | `/v1/tools/query-parse` | query parse |
| GET | `/v1/tools/evm-wallet-balance` | EVM Wallet Balance Snapshot |
| POST | `/v1/tools/evm-wallet-balance` | EVM Wallet Balance Snapshot |
| HEAD | `/v1/tools/evm-wallet-balance` | EVM Wallet Balance Snapshot |
| POST | `/v1/tools/x402-mcp-integration-kit` | x402 mcp integration kit |
| POST | `/v1/tools/x402-bazaar-search` | x402 bazaar search |
| GET | `/v1/paid/wallet-payment-activation-agent` | Wallet Payment Activation Agent |
| GET | `/v1/paid/wallet-signing-safety-pack` | Quote or buy wallet signing safety pack via GET |
| POST | `/v1/paid/wallet-signing-safety-pack` | Buy wallet signing safety pack via POST |

## Machine-readable artifacts (16)

- **OpenAPI** — https://raw.githubusercontent.com/api-evangelist/558686-xyz/refs/heads/main/openapi/558686-xyz-gpt55-model-gateway-openapi.json
- **OpenAPI** — https://gpt55.558686.xyz/openapi.json
- **Overlay** — https://raw.githubusercontent.com/api-evangelist/558686-xyz/refs/heads/main/overlays/558686-xyz-gpt55-model-gateway-overlay.yaml
- **Documentation** — https://gpt55.558686.xyz/x402/guides/ai-agent-x402-api
- **APIReference** — https://gpt55.558686.xyz/buyer-guide
- **GettingStarted** — https://gpt55.558686.xyz/x402/guides/ai-agent-x402-api
- **Pricing** — https://gpt55.558686.xyz/pricing.json
- **Postman** — https://gpt55.558686.xyz/postman/collection.json
- **PostmanCollection** — https://raw.githubusercontent.com/api-evangelist/558686-xyz/refs/heads/main/postman/558686-xyz-gpt55-postman-collection.json
- **X402** — https://gpt55.558686.xyz/.well-known/x402
- **Examples** — https://raw.githubusercontent.com/api-evangelist/558686-xyz/refs/heads/main/examples/558686-xyz-standard-chat-example.json
- **Examples** — https://raw.githubusercontent.com/api-evangelist/558686-xyz/refs/heads/main/examples/558686-xyz-translate-canary-example.json
- **RateLimits** — https://raw.githubusercontent.com/api-evangelist/558686-xyz/refs/heads/main/rate-limits/558686-xyz-rate-limits.yml
- **ErrorCatalog** — https://raw.githubusercontent.com/api-evangelist/558686-xyz/refs/heads/main/errors/558686-xyz-problem-types.yml
- **Conventions** — https://raw.githubusercontent.com/api-evangelist/558686-xyz/refs/heads/main/conventions/558686-xyz-conventions.yml
- **APIsJSON** — https://raw.githubusercontent.com/api-evangelist/558686-xyz/refs/heads/main/apis.yml

## Other gpt55-token-gateway APIs (4)

- [GPT-5.5 Utility Tools for API.market](https://apis.io/apis/558686-xyz/gpt55-utility-tools-api-market/)
- [GPT55 x402 Gateway MCP Server](https://apis.io/apis/558686-xyz/gpt55-mcp-server/)
- [GPT55 Model Gateway A2A Agent](https://apis.io/apis/558686-xyz/gpt55-a2a-agent/)
- [Sub2API OpenAI-compatible API](https://apis.io/apis/558686-xyz/sub2api-openai-compatible-api/)

## Tags

x402, AI Gateway, OpenAI-Compatible, LLM, USDC

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Profiled by [API Evangelist](https://apievangelist.com) and published on [APIs.io](https://apis.io/apis/558686-xyz/gpt55-model-gateway-api/). The API's provider profile, Kin Score and agent-readiness rating are at https://apis.io/providers/558686-xyz/.