docs: refresh MCP server guide

codex-rs/docs/codex_mcp_interface.md

@@ -8,28 +8,7 @@ This document describes Codex’s experimental MCP server interface: a JSON‑RP
 
 ## Overview
 
-Codex exposes a small set of MCP‑compatible methods to create and manage conversations, send user input, receive live events, and handle approval prompts. The types are defined in `protocol/src/mcp_protocol.rs` and re‑used by the MCP server implementation in `mcp-server/`.
-
-At a glance:
-
-- Conversations
-  - `newConversation` → start a Codex session
-  - `sendUserMessage` / `sendUserTurn` → send user input into a conversation
-  - `interruptConversation` → stop the current turn
-  - `listConversations`, `resumeConversation`, `archiveConversation`
-- Configuration and info
-  - `getUserSavedConfig`, `setDefaultModel`, `getUserAgent`, `userInfo`
-- Auth
-  - `loginApiKey`, `loginChatGpt`, `cancelLoginChatGpt`, `logoutChatGpt`, `getAuthStatus`
-- Utilities
-  - `gitDiffToRemote`, `execOneOffCommand`
-- Approvals (server → client requests)
-  - `applyPatchApproval`, `execCommandApproval`
-- Notifications (server → client)
-  - `loginChatGptComplete`, `authStatusChange`
-  - `codex/event` stream with agent events
-
-See code for full type definitions and exact shapes: `protocol/src/mcp_protocol.rs`.
+Codex now surfaces its functionality through standard MCP `tools/call` requests. A `tools/list` request returns the `codex` tool, which starts a session, and the `codex-reply` tool, which continues an existing session. The JSON schemas backing both tools are generated in `codex-rs/mcp-server/src/codex_tool_config.rs`. Codex continues to reuse the shared event types defined in `codex-rs/protocol/src/protocol.rs`. For clients that still speak the legacy JSON‑RPC API, its protocol definitions live in `codex-rs/app-server-protocol/src/protocol.rs`.
 
 ## Starting the server
 
@@ -47,78 +26,39 @@ npx @modelcontextprotocol/inspector codex mcp-server
 
 Use the separate `codex mcp` subcommand to manage configured MCP server launchers in `config.toml`.
 
-## Conversations
+## Codex tools
 
-Start a new session with optional overrides:
+Send `tools/list` to discover the available tools:
 
-Request `newConversation` params (subset):
+- `codex`: starts a new Codex session. The request `arguments` accept the fields surfaced by `CodexToolCallParam`, including the required `prompt` plus optional `model`, `profile`, `cwd`, `approval-policy`, `sandbox`, `config`, `base-instructions`, and `include-plan-tool` overrides. When the tool call finishes, the server resolves the `tools/call` request with the model’s final message in the response `content`.
+- `codex-reply`: continues an existing session. The request `arguments` must include `conversationId` and `prompt`, matching the `CodexToolCallReplyParam` schema. Use the `conversationId` returned in earlier events to correlate with the active session.
 
-- `model`: string model id (e.g. "o3", "gpt-5", "gpt-5-codex")
-- `profile`: optional named profile
-- `cwd`: optional working directory
-- `approvalPolicy`: `untrusted` | `on-request` | `on-failure` | `never`
-- `sandbox`: `read-only` | `workspace-write` | `danger-full-access`
-- `config`: map of additional config overrides
-- `baseInstructions`: optional instruction override
-- `includePlanTool` / `includeApplyPatchTool`: booleans
-
-Response: `{ conversationId, model, reasoningEffort?, rolloutPath }`
-
-Send input to the active turn:
-
-- `sendUserMessage` → enqueue items to the conversation
-- `sendUserTurn` → structured turn with explicit `cwd`, `approvalPolicy`, `sandboxPolicy`, `model`, optional `effort`, and `summary`
-
-Interrupt a running turn: `interruptConversation`.
-
-List/resume/archive: `listConversations`, `resumeConversation`, `archiveConversation`.
+Both tools run asynchronously. While a tool call is in flight, Codex streams progress via MCP notifications so the client can render intermediate output or handle approvals.
 
 ## Event stream
 
-While a conversation runs, the server sends notifications:
-
-- `codex/event` with the serialized Codex event payload. The shape matches `core/src/protocol.rs`’s `Event` and `EventMsg` types. Some notifications include a `_meta.requestId` to correlate with the originating request.
-- Auth notifications via method names `loginChatGptComplete` and `authStatusChange`.
-
-Clients should render events and, when present, surface approval requests (see next section).
+While a conversation runs, the server sends JSON‑RPC notifications whose `method` is `codex/event`. The payload embeds the serialized `Event`/`EventMsg` structures from `codex-rs/protocol/src/protocol.rs`. Notifications include `_meta.requestId` so clients can associate each event with the originating `tools/call`.
 
 ## Approvals (server → client)
 
-When Codex needs approval to apply changes or run commands, the server issues JSON‑RPC requests to the client:
+When Codex needs approval to apply a patch or run a command, it issues an MCP elicitation request (`ElicitRequest`). Patch prompts carry `PatchApprovalElicitRequestParams` and command prompts use `ExecApprovalElicitRequestParams`. Respond with JSON that includes a `decision` field whose value is one of the `ReviewDecision` strings: `approved`, `approved_for_session`, `denied`, or `abort`. These map directly to the enum defined in `codex-rs/protocol/src/protocol.rs` and determine whether Codex proceeds, auto‑approves similar actions for the current session, or halts work.
 
-- `applyPatchApproval { conversationId, callId, fileChanges, reason?, grantRoot? }`
-- `execCommandApproval { conversationId, callId, command, cwd, reason? }`
+## Example workflow
 
-The client must reply with `{ decision: "allow" | "deny" }` for each request.
-
-## Auth helpers
-
-For ChatGPT or API‑key based auth flows, the server exposes helpers:
-
-- `loginApiKey { apiKey }`
-- `loginChatGpt` → returns `{ loginId, authUrl }`; browser completes flow; then `loginChatGptComplete` notification follows
-- `cancelLoginChatGpt { loginId }`, `logoutChatGpt`, `getAuthStatus { includeToken?, refreshToken? }`
-
-## Example: start and send a message
+Start a session with the `codex` tool:
 
 ```json
-{ "jsonrpc": "2.0", "id": 1, "method": "newConversation", "params": { "model": "gpt-5", "approvalPolicy": "on-request" } }
+{ "jsonrpc": "2.0", "id": 1, "method": "tools/call", "params": { "name": "codex", "arguments": { "prompt": "List the files in this repo.", "approval-policy": "on-request", "sandbox": "workspace-write" } } }
 ```
 
-Server responds:
+The server streams `codex/event` notifications as the session runs. When the task completes, the `tools/call` response resolves with the final assistant message in its `content`. To keep going, call `codex-reply` with the returned `conversationId`:
 
 ```json
-{ "jsonrpc": "2.0", "id": 1, "result": { "conversationId": "c7b0…", "model": "gpt-5", "rolloutPath": "/path/to/rollout.jsonl" } }
+{ "jsonrpc": "2.0", "id": 2, "method": "tools/call", "params": { "name": "codex-reply", "arguments": { "conversationId": "c7b0…", "prompt": "Great, please open README.md." } } }
 ```
 
-Then send input:
-
-```json
-{ "jsonrpc": "2.0", "id": 2, "method": "sendUserMessage", "params": { "conversationId": "c7b0…", "items": [{ "type": "text", "text": "Hello Codex" }] } }
-```
-
-While processing, the server emits `codex/event` notifications containing agent output, approvals, and status updates.
+Any approval prompts during either call arrive as elicitation requests. Reply with the desired `ReviewDecision` to allow, deny, or pause execution.
 
 ## Compatibility and stability
 
-This interface is experimental. Method names, fields, and event shapes may evolve. For the authoritative schema, consult `protocol/src/mcp_protocol.rs` and the corresponding server wiring in `mcp-server/`.
+This interface is experimental. Tool schemas, fields, and event shapes may evolve. For the authoritative definitions, consult `codex-rs/mcp-server/src/codex_tool_config.rs`, the shared event types in `codex-rs/protocol/src/protocol.rs`, and the legacy JSON‑RPC spec in `codex-rs/app-server-protocol/src/protocol.rs`.