refactor: consolidate MCP features and embed stdio server in det-cli

Simplify from 3 features (mcp-stdio, mcp-http, cli) to 2:
- `mcp`: HTTP server embedded in GUI app
- `cli`: det-cli binary with in-process MCP and `serve` subcommand

Remove standalone `dash-evo-tool-mcp` binary — `det-cli serve` replaces
it as the MCP stdio server for Claude Desktop and AI agents.

Update docs (MCP.md, CLI.md, CONTRIBUTING.md) to reflect new layout.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: lklimek

CONTRIBUTING.md

@@ -60,6 +60,21 @@ Run the application:
 cargo run
 ```
 
+## Feature flags
+
+| Feature | Description |
+|---|---|
+| `mcp` | MCP HTTP server embedded in the GUI app (see [docs/MCP.md](docs/MCP.md)) |
+| `cli` | `det-cli` command-line client with in-process MCP service (see [docs/CLI.md](docs/CLI.md)) |
+| `testing` | Test-only utilities |
+
+Build with a specific feature:
+
+```shell
+cargo build --features mcp        # GUI app + HTTP MCP server
+cargo build --features cli         # det-cli binary
+```
+
 ## Code quality
 
 Before submitting changes, run the formatter and linter:

Cargo.lock

@@ -94,19 +94,13 @@ raw-cpuid = "11.5.0"
 
 [features]
 testing = []
-mcp-stdio = ["dep:rmcp", "rmcp/server", "rmcp/macros", "rmcp/transport-io"]
-mcp-http = ["dep:rmcp", "rmcp/server", "rmcp/macros", "rmcp/transport-streamable-http-server", "dep:axum", "dep:subtle"]
-cli = ["dep:rmcp", "rmcp/client", "rmcp/transport-child-process", "rmcp/transport-streamable-http-client-reqwest", "dep:clap", "dep:clap_complete"]
+mcp = ["dep:rmcp", "rmcp/server", "rmcp/macros", "rmcp/transport-streamable-http-server", "dep:axum", "dep:subtle"]
+cli = ["dep:rmcp", "rmcp/server", "rmcp/macros", "rmcp/client", "rmcp/transport-io", "rmcp/transport-streamable-http-client-reqwest", "dep:clap", "dep:clap_complete"]
 
 [dev-dependencies]
 egui_kittest = { version = "0.33.3", features = ["eframe"] }
 tokio-shared-rt = "=0.1.0"
 
-[[bin]]
-name = "dash-evo-tool-mcp"
-path = "src/bin/mcp_server.rs"
-required-features = ["mcp-stdio"]
-
 [[bin]]
 name = "det-cli"
 path = "src/bin/det_cli.rs"
@@ -123,7 +117,7 @@ debug = "line-tables-only"
 
 [lints.rust.unexpected_cfgs]
 level = "warn"
-check-cfg = ["cfg(tokio_unstable)", "cfg(feature, values(\"testing\", \"mcp-stdio\", \"mcp-http\", \"cli\"))"]
+check-cfg = ["cfg(tokio_unstable)", "cfg(feature, values(\"testing\", \"mcp\", \"cli\"))"]
 
 [lints.clippy]
 uninlined_format_args = "allow"

Cargo.toml

@@ -1,15 +1,13 @@
 # det-cli
 
-`det-cli` is the command-line client for Dash Evo Tool's MCP server. Use it to call wallet and core operations from scripts and terminals without opening the GUI.
+`det-cli` is the command-line interface for Dash Evo Tool. It provides both a CLI client for calling MCP tools and a built-in MCP stdio server.
 
 ## Build
 
 ```bash
 cargo build --features cli
 ```
 
-The binary is `det-cli` in the Cargo output directory.
-
 ## Configuration
 
 `det-cli` reads the app's `.env` file automatically on startup — the same file used by the GUI. No separate configuration is needed.
@@ -22,6 +20,14 @@ Config precedence (highest to lowest):
 
 ## Connection modes
 
+### In-process (default)
+
+When no `MCP_API_KEY` is configured, `det-cli` runs the MCP service in-process. No running GUI app or separate server required.
+
+```bash
+det-cli tools
+```
+
 ### HTTP
 
 Used automatically when `MCP_API_KEY` is available (from `.env` or shell). Connects to the running GUI app's MCP HTTP server.
@@ -36,21 +42,11 @@ The server address defaults to `http://{MCP_LISTEN}/mcp`, or `http://127.0.0.1:9
 det-cli --addr http://127.0.0.1:9000/mcp tools
 ```
 
-### Stdio (default when no API key)
-
-When no `MCP_API_KEY` is configured, `det-cli` spawns `dash-evo-tool-mcp` as a child process and communicates via stdin/stdout. No running GUI app required.
-
-`dash-evo-tool-mcp` must be built (`cargo build --features mcp-stdio`) and on `PATH`.
-
-Force stdio mode explicitly with `--standalone`:
-
-```bash
-det-cli --standalone tools
-```
+Force in-process mode with `--standalone` even when an API key is present.
 
 ## Usage
 
-Running `det-cli` with no subcommand lists available tools (same as `det-cli tools`).
+Running `det-cli` with no subcommand lists available tools.
 
 ### `tools` — list available tools
 
@@ -69,21 +65,22 @@ det-cli call <tool-name> [key=value ...]
 Parameter values are parsed as JSON first, falling back to plain strings.
 
 ```bash
-# No parameters
 det-cli call list_wallets
-
-# String parameter
 det-cli call generate_receive_address wallet_id=my-wallet
-
-# JSON parameter (boolean)
 det-cli call some_tool enabled=true
 ```
 
 Exit code is non-zero when the tool returns an error.
 
-### `completion <shell>` — generate shell completion
+### `serve` — run as MCP stdio server
 
-Generates a completion script for the given shell. Supported: `bash`, `zsh`, `fish`, `powershell`.
+```bash
+det-cli serve
+```
+
+Runs an MCP server over stdin/stdout for use with Claude Desktop, AI agents, or other MCP clients. See [MCP.md](MCP.md) for Claude Desktop configuration.
+
+### `completion <shell>` — generate shell completion
 
 ```bash
 det-cli completion bash
@@ -94,21 +91,20 @@ det-cli completion zsh
 
 The tool list is cached automatically when you run `det-cli` or `det-cli tools`. The cache includes the server version and is invalidated when the version changes.
 
-`det-cli --help` appends the cached tool list to the standard help output. If the cache is empty or stale, run `det-cli` once to populate it.
+`det-cli --help` appends the cached tool list to the standard help output.
 
 ## Shell completion setup
 
 ### Bash
 
 ```bash
-# Add completion to your shell session
 source <(det-cli completion bash)
 
 # Or add permanently to ~/.bashrc
 echo 'source <(det-cli completion bash)' >> ~/.bashrc
 ```
 
-The bash completion script includes a dynamic completer for tool names in `det-cli call`. It reads from the local cache. Requires `jq` for dynamic tool name completion.
+The bash completion includes dynamic tool name completion for `det-cli call`. Requires `jq`.
 
 ### Zsh
 
@@ -119,16 +115,18 @@ det-cli completion zsh > "${fpath[1]}/_det-cli"
 ## Examples
 
 ```bash
-# List wallets loaded in the app (reads MCP_API_KEY from .env)
+# List wallets (in-process, no server needed)
 det-cli call list_wallets
 
-# Generate a receive address (use alias or hex seed hash)
+# Generate a receive address
 det-cli call generate_receive_address wallet_id=savings
 
 # List wallets in Dash Core
 det-cli call list_core_wallets
 
-# Stdio mode (no GUI required)
-det-cli --standalone call list_wallets
-MCP_NETWORK=testnet det-cli --standalone call list_wallets
+# Use testnet
+MCP_NETWORK=testnet det-cli call list_wallets
+
+# Run as stdio MCP server for Claude Desktop
+det-cli serve
 ```

docs/CLI.md

@@ -1,10 +1,8 @@
 # MCP Server
 
-Dash Evo Tool exposes wallet and core operations via the [Model Context Protocol](https://modelcontextprotocol.io/). Two transport modes are available, each behind its own Cargo feature flag.
+Dash Evo Tool exposes wallet and core operations via the [Model Context Protocol](https://modelcontextprotocol.io/). Two modes are available:
 
-## Transport modes
-
-### HTTP (`mcp-http`)
+## HTTP mode (`mcp` feature)
 
 Embedded in the GUI app. Shares the running app's `AppContext` and follows network switches in real time.
 
@@ -14,22 +12,21 @@ Routes:
 - `GET /health` — unauthenticated liveness check, returns `OK`
 - `POST /mcp` — MCP protocol endpoint, requires `Authorization: Bearer <key>`
 
-### Stdio (`mcp-stdio`)
+Build: `cargo build --features mcp`
 
-Standalone binary `dash-evo-tool-mcp`. No GUI. Communicates via stdin/stdout using the MCP protocol. `AppContext` is initialized lazily on the first tool call, reading the same `.env` and database as the GUI app.
+## Stdio mode (via `det-cli serve`)
 
-## Building
+The `det-cli` binary includes a built-in MCP stdio server. No separate binary needed.
 
 ```bash
-# HTTP transport (GUI app)
-cargo build --features mcp-http
+det-cli serve
+```
 
-# Stdio transport (standalone binary)
-cargo build --features mcp-stdio
+Communicates via stdin/stdout using the MCP protocol. `AppContext` is initialized lazily on the first tool call, reading the same `.env` and database as the GUI app. Configure the network via `MCP_NETWORK` env var.
 
-# CLI client (see docs/CLI.md)
-cargo build --features cli
-```
+Build: `cargo build --features cli`
+
+See [CLI.md](CLI.md) for full `det-cli` documentation.
 
 ## Environment variables
 
@@ -59,7 +56,8 @@ Add to `claude_desktop_config.json`:
 {
   "mcpServers": {
     "dash-evo-tool": {
-      "command": "dash-evo-tool-mcp",
+      "command": "det-cli",
+      "args": ["serve"],
       "env": {
         "MCP_NETWORK": "mainnet"
       }
@@ -68,7 +66,7 @@ Add to `claude_desktop_config.json`:
 }
 ```
 
-`dash-evo-tool-mcp` must be on `PATH` (or use the full path to the binary).
+`det-cli` must be on `PATH` (or use the full path to the binary).
 
 ### HTTP with curl