Backplane Docs https://backplane.gsmlg.net

Backplane Docs

Public gateway references for MCP tools, model traffic, skills, agent setup, and authentication.

Tools/mcp

MCP Hub

Streamable HTTP, OAuth discovery, and namespaced tools.

Models/v1

LLM proxy

Compatible model APIs with resource-bound access tokens.

MCP hub

Connect ChatGPT and other MCP clients to Backplane's resource-bound tool gateway.

LLM proxy

Authorize API clients for Backplane's separate /v1 resource, then call model endpoints with a resource-bound bearer token.

Google GenAI

Use the native Gemini Developer API through Backplane, or keep the existing Google Antigravity (agy) subscription route explicit and separate.

Skills library

Serve, import, export, and browse reusable agent skills through the public Skills API and MCP tools.

Agent setup

Use the configured Backplane origin for ChatGPT, Claude Code, and Codex without embedding real credentials.

Authentication

Manage predefined OAuth clients and troubleshoot the separate MCP and LLM protected resources.

MCP hub Open section

MCP hub

Connect ChatGPT and other MCP clients to Backplane's resource-bound tool gateway.

One protected MCP resource

https://backplane.gsmlg.net/mcp is the canonical Streamable HTTP endpoint. An unauthenticated request returns a WWW-Authenticate challenge that points to https://backplane.gsmlg.net/.well-known/oauth-protected-resource/mcp.

Scoped access

Assign the same MCP tool scopes to the predefined client and the signing-in user. Backplane exposes permitted tools with stable prefix::tool names.

Reference


                    POST /mcp


                    GET /mcp


                    DELETE /mcp


                    GET /.well-known/oauth-protected-resource/mcp

LLM proxy Open section

LLM proxy

Authorize API clients for Backplane's separate /v1 resource, then call model endpoints with a resource-bound bearer token.

LLM scopes

Grant llm::models for model discovery and llm::invoke for inference operations. Request only the scopes the client and user share.

Existing credentials remain valid

Resource OAuth is additive compatibility: existing PAT and legacy bearer access continue under the deployment's configured authentication policy.

Reference


                    GET /v1


                    GET /v1/models


                    GET /v1/codex/models


                    POST /v1/messages


                    POST /v1/chat/completions


                    POST /v1/responses


                    GET /.well-known/oauth-protected-resource/v1

Google GenAI Open section

Google GenAI and agy

Use the native Gemini Developer API through Backplane, or keep the existing Google Antigravity (agy) subscription route explicit and separate.

Gemini Developer API

The google-gemini-developer provider uses the official Gemini GenerateContent API at /v1beta. Configure an API-key credential in the admin provider settings; Backplane injects it upstream and never forwards caller credentials. Clients may authenticate with Authorization: Bearer, x-api-key, or the Google SDK's x-goog-api-key compatibility header using the same Backplane client token.

Native Google GenerateContent operations

The native Google surface supports model listing, model details, generateContent, streamGenerateContent with alt=sse, and countTokens. Use the Google-shaped request and response bodies; this route does not silently translate to OpenAI.

Google Antigravity (agy)

The google-antigravity provider is a separate OAuth subscription surface for the existing agy workflow. It uses its own native Cloud Code protocol and credential; do not reuse a Gemini API key or treat Antigravity as the public Gemini Developer API.

Reference


                    GET /v1beta/models


                    GET /v1beta/models/:model


                    POST /v1beta/models/:model:generateContent


                    POST /v1beta/models/:model:streamGenerateContent?alt=sse


                    POST /v1beta/models/:model:countTokens

Skills library Open section

Skills library

Serve, import, export, and browse reusable agent skills through the public Skills API and MCP tools.

Skill archive routes

Use /skills to list or create records, /skills/export for a bundle, and /skills/:slug/archive for a single archive.

Managed service tools

The skills managed service exposes skill discovery and retrieval through MCP for connected agents.

Host-agent support

The host-agent socket can synchronize local skill and memory context with Backplane.

Reference


                    GET /skills


                    POST /skills


                    GET /skills/export


                    POST /skills/import


                    GET /skills/:slug


                    GET /skills/:slug/archive


                    DELETE /skills/:slug

Agent setup Open section

Agent setup

Use the configured Backplane origin for ChatGPT, Claude Code, and Codex without embedding real credentials.

Keep endpoints distinct

MCP clients connect to https://backplane.gsmlg.net/mcp; model clients use https://backplane.gsmlg.net/v1. Resource-bound OAuth access tokens are audience-specific, so use separate $MCP_ACCESS_TOKEN and $LLM_ACCESS_TOKEN values. PAT and legacy credentials follow the configured compatibility policy.

Reference


                    ChatGPT


                    Claude Code


                    Codex


                    MCP /mcp


                    LLM API /v1

Authentication Open section

Authentication

Manage predefined OAuth clients and troubleshoot the separate MCP and LLM protected resources.

Separate resource audiences

https://backplane.gsmlg.net/mcp and https://backplane.gsmlg.net/v1 are separate OAuth audiences. Resource-bound OAuth access tokens are audience-specific: a token issued for one resource is not valid for the other. PAT and legacy credentials follow the configured compatibility policy.

Credential header compatibility

All protected API resources accept Authorization: Bearer <token>. x-api-key is an equivalent Backplane client-token alias. Google GenAI clients may also use x-goog-api-key on /v1beta; send only one credential header per request.

Predefined clients and PKCE

Use predefined OAuth clients. ChatGPT uses a confidential client with its exact registered callback and PKCE S256; the client secret is displayed only once.

Refresh and revocation

A refresh token request that omits resource inherits its original resource, supporting durable ChatGPT connectivity across reconnects. Revoke access at https://backplane.gsmlg.net/oauth/revoke.

HTTPS and troubleshooting

OAuth protected resources require HTTPS outside the explicit local development override. invalid_target means the requested resource is missing, repeated, unsupported, or disallowed; invalid_token means the bearer token is invalid or bound to the wrong audience; insufficient_scope means the valid token lacks the required operation scope.

Reference


                    GET /oauth/authorize


                    POST /oauth/token


                    POST /oauth/revoke


                    GET /.well-known/oauth-protected-resource/mcp


                    GET /.well-known/oauth-protected-resource/v1