mcp: Remove Model Context Protocol support

Delete the entire MCP server implementation including:
- cli/src/services/mcp.rs (stdio server, Smart Cache service layer)
- Smart Cache database bootstrap, migration, and file caching
- MCP configuration files (.mcp.json, mcp.pkl)
- All MCP-related context documentation

Author: davidabram

.opencode/opencode.json

@@ -2,12 +2,5 @@
   "$schema": "https://opencode.ai/config.json",
   "plugin": [
     "./plugins/sce-bash-policy.js"
-  ],
-  "mcp": {
-    "sce": {
-      "type": "local",
-      "command": ["sce", "mcp"],
-      "enabled": true
-    }
-  }
+  ]
 }

.opencode/package.json

@@ -0,0 +1,5 @@
+{
+  "dependencies": {
+    "@opencode-ai/plugin": "1.2.27"
+  }
+}

cli/Cargo.lock

@@ -26,8 +26,6 @@ serde_json = "1"
 sha2 = "0.10"
 tokio = { version = "1", default-features = false, features = ["rt", "io-util"] }
 tracing = "0.1"
-rmcp = { version = "1", features = ["server", "transport-io"] }
-schemars = "1"
 tracing-opentelemetry = "0.29"
 tracing-subscriber = { version = "0.3", features = ["registry"] }
 turso = "0"

cli/Cargo.toml

@@ -110,7 +110,6 @@ enum Command {
     Config(services::config::ConfigSubcommand),
     Setup(services::setup::SetupRequest),
     Doctor(services::doctor::DoctorRequest),
-    Mcp,
     Hooks(services::hooks::HookSubcommand),
     Trace(services::trace::TraceRequest),
     Sync(services::sync::SyncRequest),
@@ -127,7 +126,6 @@ impl Command {
             Self::Config(_) => services::config::NAME,
             Self::Setup(_) => services::setup::NAME,
             Self::Doctor(_) => services::doctor::NAME,
-            Self::Mcp => services::mcp::NAME,
             Self::Hooks(_) => services::hooks::NAME,
             Self::Trace(_) => services::trace::NAME,
             Self::Sync(_) => services::sync::NAME,
@@ -185,6 +183,10 @@ fn write_stdout_payload<W>(writer: &mut W, payload: &str) -> Result<(), Classifi
 where
     W: Write,
 {
+    if payload.is_empty() {
+        return Ok(());
+    }
+
     writeln!(writer, "{payload}").map_err(|error| {
         ClassifiedError::runtime(format!("Failed to write command output to stdout: {error}"))
     })
@@ -268,7 +270,7 @@ where
             &[("command", command.name())],
         );
 
-        match dispatch(&command) {
+        match dispatch(&command, &logger) {
             Ok(payload) => {
                 logger.info(
                     "sce.command.completed",
@@ -469,7 +471,6 @@ fn convert_clap_command(command: cli_schema::Commands) -> Result<Command, Classi
             },
             format: convert_output_format(format),
         })),
-        cli_schema::Commands::Mcp => Ok(Command::Mcp),
         cli_schema::Commands::Hooks { subcommand } => convert_hooks_subcommand(subcommand),
         cli_schema::Commands::Trace { subcommand } => convert_trace_subcommand(subcommand),
         cli_schema::Commands::Sync { format } => Ok(Command::Sync(services::sync::SyncRequest {
@@ -654,7 +655,10 @@ fn convert_trace_subcommand(
     }
 }
 
-fn dispatch(command: &Command) -> Result<String, ClassifiedError> {
+fn dispatch(
+    command: &Command,
+    _logger: &services::observability::Logger,
+) -> Result<String, ClassifiedError> {
     match command {
         Command::Help => Ok(command_surface::help_text()),
         Command::HelpText { text, .. } => Ok(text.clone()),
@@ -716,8 +720,6 @@ fn dispatch(command: &Command) -> Result<String, ClassifiedError> {
         }
         Command::Doctor(request) => services::doctor::run_doctor(*request)
             .map_err(|error| ClassifiedError::runtime(error.to_string())),
-        Command::Mcp => services::mcp::run_mcp_server_blocking()
-            .map_err(|error| ClassifiedError::runtime(error.to_string())),
         Command::Hooks(subcommand) => services::hooks::run_hooks_subcommand(subcommand.clone())
             .map_err(|error| ClassifiedError::runtime(error.to_string())),
         Command::Trace(request) => services::trace::run_trace_subcommand(request.clone())
@@ -839,6 +841,15 @@ mod tests {
         assert!(stderr.contains("Try:"));
     }
 
+    #[test]
+    fn empty_payload_does_not_write_stdout() {
+        let mut stdout = Vec::new();
+
+        super::write_stdout_payload(&mut stdout, "").expect("empty payload should be skipped");
+
+        assert!(stdout.is_empty());
+    }
+
     #[test]
     fn parse_failure_stderr_contract_is_exact_and_deterministic() {
         let mut first_stdout = Vec::new();
@@ -1265,10 +1276,10 @@ mod tests {
     }
 
     #[test]
-    fn parser_routes_mcp() {
-        let command = parse_command(vec!["sce".to_string(), "mcp".to_string()])
-            .expect("command should parse");
-        assert_eq!(command, Command::Mcp);
+    fn parser_rejects_mcp() {
+        let error = parse_command(vec!["sce".to_string(), "mcp".to_string()])
+            .expect_err("mcp should be rejected");
+        assert!(error.to_string().contains("Unknown command 'mcp'"));
     }
 
     #[test]

cli/src/app.rs

@@ -95,9 +95,6 @@ pub enum Commands {
         format: OutputFormat,
     },
 
-    #[command(about = "Host MCP Smart Cache Engine server for cache-aware file reads")]
-    Mcp,
-
     #[command(about = "Run git-hook runtime entrypoints for local Agent Trace flows")]
     Hooks {
         #[command(subcommand)]
@@ -830,15 +827,6 @@ mod tests {
         }
     }
 
-    #[test]
-    fn parse_mcp() {
-        let cli = Cli::try_parse_from(["sce", "mcp"]).expect("mcp should parse");
-        match cli.command {
-            Some(Commands::Mcp) => {}
-            _ => panic!("Expected Mcp command"),
-        }
-    }
-
     #[test]
     fn parse_completion_bash() {
         let cli = Cli::try_parse_from(["sce", "completion", "--shell", "bash"])

cli/src/cli_schema.rs

@@ -39,11 +39,6 @@ pub const COMMANDS: &[CommandContract] = &[
         status: ImplementationStatus::Implemented,
         purpose: "Authenticate with WorkOS and inspect local auth state",
     },
-    CommandContract {
-        name: services::mcp::NAME,
-        status: ImplementationStatus::Implemented,
-        purpose: "Host MCP Smart Cache Engine server for cache-aware file reads",
-    },
     CommandContract {
         name: services::hooks::NAME,
         status: ImplementationStatus::Implemented,
@@ -97,14 +92,13 @@ Setup usage:\n  sce setup [--opencode|--claude|--both] [--non-interactive] [--ho
 Doctor usage:\n  sce doctor [--fix] [--all-databases] [--format <text|json>]\n\n\
 Auth usage:\n  sce auth <login|logout|status> [--format <text|json>]\n\n\
 Completion usage:\n  sce completion --shell <bash|zsh|fish>\n\n\
-MCP usage:\n  sce mcp\n\n\
 Trace usage:\n  sce trace prompts <commit-sha> [--format <text|json>|--json]\n\n\
 Output format contract:\n  Supported commands accept --format <text|json>\n\n\
 Examples:\n  sce setup\n  sce setup --opencode --non-interactive --hooks\n  sce setup --hooks --repo ../demo-repo\n  sce auth status\n  sce auth login --format json\n  sce trace prompts abc1234\n  sce trace prompts abc1234 --json\n  sce doctor --format json\n  sce doctor --all-databases --format json\n  sce doctor --fix\n  sce version --format json\n\n\
 Commands:\n{command_rows}\n\n\
 Setup defaults to interactive target selection when no setup target flag is passed, and installs hooks in the same run.\n\
 Use '--hooks' to install required git hooks for the current repository or '--repo <path>' for a specific repository.\n\
-`setup`, `doctor`, `auth`, `hooks`, `trace`, `mcp`, `version`, and `completion` are implemented; `sync` remains placeholder-oriented.\n"
+`setup`, `doctor`, `auth`, `hooks`, `trace`, `version`, and `completion` are implemented; `sync` remains placeholder-oriented.\n"
     )
 }
 

cli/src/command_surface.rs

@@ -77,7 +77,6 @@ mod tests {
         assert!(output.contains("config"));
         assert!(output.contains("setup"));
         assert!(output.contains("doctor"));
-        assert!(output.contains("mcp"));
         assert!(output.contains("hooks"));
         assert!(output.contains("sync"));
         assert!(output.contains("version"));