feat: add docker mcp gateway

go.mod

@@ -2,6 +2,8 @@ module github.com/charmbracelet/crush
 
 go 1.25.0
 
+replace charm.land/fantasy => ../../fantasy
+
 require (
 	charm.land/bubbles/v2 v2.0.0-rc.1
 	charm.land/bubbletea/v2 v2.0.0-rc.2.0.20251126220703-2a0096c500a7
@@ -70,7 +72,7 @@ require (
 	github.com/Azure/azure-sdk-for-go/sdk/internal v1.10.0 // indirect
 	github.com/RealAlexandreAI/json-repair v0.0.14 // indirect
 	github.com/andybalholm/cascadia v1.3.3 // indirect
-	github.com/aws/aws-sdk-go-v2 v1.39.6 // indirect
+	github.com/aws/aws-sdk-go-v2 v1.40.0 // indirect
 	github.com/aws/aws-sdk-go-v2/aws/protocol/eventstream v1.6.3 // indirect
 	github.com/aws/aws-sdk-go-v2/config v1.27.27 // indirect
 	github.com/aws/aws-sdk-go-v2/credentials v1.17.27 // indirect
@@ -169,7 +171,7 @@ require (
 	golang.org/x/term v0.37.0 // indirect
 	golang.org/x/time v0.12.0 // indirect
 	google.golang.org/api v0.239.0 // indirect
-	google.golang.org/genai v1.34.0 // indirect
+	google.golang.org/genai v1.36.0 // indirect
 	google.golang.org/genproto/googleapis/rpc v0.0.0-20250603155806-513f23925822 // indirect
 	google.golang.org/grpc v1.74.2 // indirect
 	google.golang.org/protobuf v1.36.10 // indirect

go.sum

@@ -2,8 +2,6 @@ charm.land/bubbles/v2 v2.0.0-rc.1 h1:EiIFVAc3Zi/yY86td+79mPhHR7AqZ1OxF+6ztpOCRaM
 charm.land/bubbles/v2 v2.0.0-rc.1/go.mod h1:5AbN6cEd/47gkEf8TgiQ2O3RZ5QxMS14l9W+7F9fPC4=
 charm.land/bubbletea/v2 v2.0.0-rc.2.0.20251126220703-2a0096c500a7 h1:3qsObfEm0WuACFhe3MSTPX8QByjVcjWkZDO4o2VWFpc=
 charm.land/bubbletea/v2 v2.0.0-rc.2.0.20251126220703-2a0096c500a7/go.mod h1:IXFmnCnMLTWw/KQ9rEatSYqbAPAYi8kA3Yqwa1SFnLk=
-charm.land/fantasy v0.3.2 h1:yHTsSZ25LcICMRw3xzdz3OkaZtDQch+B5ljJo17HxgU=
-charm.land/fantasy v0.3.2/go.mod h1:sV8Ns/JTJHOaYOHPgVRDugMheAyxsW/nmdpVGrycYEk=
 charm.land/lipgloss/v2 v2.0.0-beta.3.0.20251119143523-0334bb4562ca h1:6bVc8OFotCS4sS7HKqxTudP7yn8Y0ODR6df2pdlY/+s=
 charm.land/lipgloss/v2 v2.0.0-beta.3.0.20251119143523-0334bb4562ca/go.mod h1:XSJjv7DaH4zd1Y27kZis295RkEj9OFR9zh2WffQQsKQ=
 charm.land/x/vcr v0.1.1 h1:PXCFMUG0rPtyk35rhfzYCJEduOzWXCIbrXTFq4OF/9Q=
@@ -44,8 +42,8 @@ github.com/andybalholm/cascadia v1.3.3 h1:AG2YHrzJIm4BZ19iwJ/DAua6Btl3IwJX+VI4kk
 github.com/andybalholm/cascadia v1.3.3/go.mod h1:xNd9bqTn98Ln4DwST8/nG+H0yuB8Hmgu1YHNnWw0GeA=
 github.com/atotto/clipboard v0.1.4 h1:EH0zSVneZPSuFR11BlR9YppQTVDbh5+16AmcJi4g1z4=
 github.com/atotto/clipboard v0.1.4/go.mod h1:ZY9tmq7sm5xIbd9bOK4onWV4S6X0u6GY7Vn0Yu86PYI=
-github.com/aws/aws-sdk-go-v2 v1.39.6 h1:2JrPCVgWJm7bm83BDwY5z8ietmeJUbh3O2ACnn+Xsqk=
-github.com/aws/aws-sdk-go-v2 v1.39.6/go.mod h1:c9pm7VwuW0UPxAEYGyTmyurVcNrbF6Rt/wixFqDhcjE=
+github.com/aws/aws-sdk-go-v2 v1.40.0 h1:/WMUA0kjhZExjOQN2z3oLALDREea1A7TobfuiBrKlwc=
+github.com/aws/aws-sdk-go-v2 v1.40.0/go.mod h1:c9pm7VwuW0UPxAEYGyTmyurVcNrbF6Rt/wixFqDhcjE=
 github.com/aws/aws-sdk-go-v2/aws/protocol/eventstream v1.6.3 h1:tW1/Rkad38LA15X4UQtjXZXNKsCgkshC3EbmcUmghTg=
 github.com/aws/aws-sdk-go-v2/aws/protocol/eventstream v1.6.3/go.mod h1:UbnqO+zjqk3uIt9yCACHJ9IVNhyhOCnYk8yA19SAWrM=
 github.com/aws/aws-sdk-go-v2/config v1.27.27 h1:HdqgGt1OAP0HkEDDShEl0oSYa9ZZBSOmKpdpsDMdO90=
@@ -457,8 +455,8 @@ golang.org/x/tools v0.38.0/go.mod h1:yEsQ/d/YK8cjh0L6rZlY8tgtlKiBNTL14pGDJPJpYQs
 golang.org/x/xerrors v0.0.0-20190717185122-a985d3407aa7/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 google.golang.org/api v0.239.0 h1:2hZKUnFZEy81eugPs4e2XzIJ5SOwQg0G82bpXD65Puo=
 google.golang.org/api v0.239.0/go.mod h1:cOVEm2TpdAGHL2z+UwyS+kmlGr3bVWQQ6sYEqkKje50=
-google.golang.org/genai v1.34.0 h1:lPRJRO+HqRX1SwFo1Xb/22nZ5MBEPUbXDl61OoDxlbY=
-google.golang.org/genai v1.34.0/go.mod h1:7pAilaICJlQBonjKKJNhftDFv3SREhZcTe9F6nRcjbg=
+google.golang.org/genai v1.36.0 h1:sJCIjqTAmwrtAIaemtTiKkg2TO1RxnYEusTmEQ3nGxM=
+google.golang.org/genai v1.36.0/go.mod h1:A3kkl0nyBjyFlNjgxIwKq70julKbIxpSxqKO5gw/gmk=
 google.golang.org/genproto/googleapis/rpc v0.0.0-20250603155806-513f23925822 h1:fc6jSaCT0vBduLYZHYrBBNY4dsWuvgyff9noRNDdBeE=
 google.golang.org/genproto/googleapis/rpc v0.0.0-20250603155806-513f23925822/go.mod h1:qQ0YXyHHx3XkvlzUtpXDkS29lDSafHMZBAZDc03LQ3A=
 google.golang.org/grpc v1.74.2 h1:WoosgB65DlWVC9FqI82dGsZhWFNBSLjQ84bjROOpMu4=

internal/agent/agent.go

@@ -212,6 +212,9 @@ func (a *sessionAgent) Run(ctx context.Context, call SessionAgentCall) (*fantasy
 				prepared.Messages[i].ProviderOptions = nil
 			}
 
+			// Use latest tools (updated by SetTools when MCP tools change).
+			prepared.Tools = a.tools
+
 			queuedCalls, _ := a.messageQueue.Get(call.SessionID)
 			a.messageQueue.Del(call.SessionID)
 			for _, queued := range queuedCalls {

internal/agent/coordinator.go

@@ -52,6 +52,7 @@ type Coordinator interface {
 	Summarize(context.Context, string) error
 	Model() Model
 	UpdateModels(ctx context.Context) error
+	RefreshTools(ctx context.Context) error
 }
 
 type coordinator struct {
@@ -742,6 +743,21 @@ func (c *coordinator) UpdateModels(ctx context.Context) error {
 	return nil
 }
 
+func (c *coordinator) RefreshTools(ctx context.Context) error {
+	agentCfg, ok := c.cfg.Agents[config.AgentCoder]
+	if !ok {
+		return errors.New("coder agent not configured")
+	}
+
+	tools, err := c.buildTools(ctx, agentCfg)
+	if err != nil {
+		return err
+	}
+	c.currentAgent.SetTools(tools)
+	slog.Debug("refreshed agent tools", "count", len(tools))
+	return nil
+}
+
 func (c *coordinator) QueuedPrompts(sessionID string) int {
 	return c.currentAgent.QueuedPrompts(sessionID)
 }

internal/agent/tools/mcp/init.go

@@ -189,6 +189,80 @@ func Initialize(ctx context.Context, permissions permission.Service, cfg *config
 	wg.Wait()
 }
 
+// InitializeSingle initializes a single MCP client by name.
+func InitializeSingle(ctx context.Context, name string, cfg *config.Config) error {
+	m, exists := cfg.MCP[name]
+	if !exists {
+		return fmt.Errorf("mcp '%s' not found in configuration", name)
+	}
+
+	if m.Disabled {
+		updateState(name, StateDisabled, nil, nil, Counts{})
+		slog.Debug("skipping disabled mcp", "name", name)
+		return nil
+	}
+
+	// Set initial starting state.
+	updateState(name, StateStarting, nil, nil, Counts{})
+
+	// createSession handles its own timeout internally.
+	session, err := createSession(ctx, name, m, cfg.Resolver())
+	if err != nil {
+		return err
+	}
+
+	tools, err := getTools(ctx, session)
+	if err != nil {
+		slog.Error("error listing tools", "error", err)
+		updateState(name, StateError, err, nil, Counts{})
+		session.Close()
+		return err
+	}
+
+	prompts, err := getPrompts(ctx, session)
+	if err != nil {
+		slog.Error("error listing prompts", "error", err)
+		updateState(name, StateError, err, nil, Counts{})
+		session.Close()
+		return err
+	}
+
+	updateTools(name, tools)
+	updatePrompts(name, prompts)
+	sessions.Set(name, session)
+
+	updateState(name, StateConnected, nil, session, Counts{
+		Tools:   len(tools),
+		Prompts: len(prompts),
+	})
+
+	return nil
+}
+
+// DisableSingle disables and closes a single MCP client by name.
+func DisableSingle(name string) error {
+	session, ok := sessions.Get(name)
+	if ok {
+		if err := session.Close(); err != nil &&
+			!errors.Is(err, io.EOF) &&
+			!errors.Is(err, context.Canceled) &&
+			err.Error() != "signal: killed" {
+			slog.Warn("error closing mcp session", "name", name, "error", err)
+		}
+		sessions.Del(name)
+	}
+
+	// Clear tools and prompts for this MCP.
+	updateTools(name, nil)
+	updatePrompts(name, nil)
+
+	// Update state to disabled.
+	updateState(name, StateDisabled, nil, nil, Counts{})
+
+	slog.Info("Disabled mcp client", "name", name)
+	return nil
+}
+
 func getOrRenewClient(ctx context.Context, name string) (*mcp.ClientSession, error) {
 	sess, ok := sessions.Get(name)
 	if !ok {

internal/config/docker_mcp.go

@@ -0,0 +1,75 @@
+package config
+
+import (
+	"context"
+	"fmt"
+	"os/exec"
+	"time"
+)
+
+// DockerMCPName is the name of the Docker MCP configuration.
+const DockerMCPName = "crush_docker"
+
+// IsDockerMCPAvailable checks if Docker MCP is available by running
+// 'docker mcp version'.
+func IsDockerMCPAvailable() bool {
+	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
+	defer cancel()
+
+	cmd := exec.CommandContext(ctx, "docker", "mcp", "version")
+	err := cmd.Run()
+	return err == nil
+}
+
+// IsDockerMCPEnabled checks if Docker MCP is already configured.
+func (c *Config) IsDockerMCPEnabled() bool {
+	if c.MCP == nil {
+		return false
+	}
+	_, exists := c.MCP[DockerMCPName]
+	return exists
+}
+
+// EnableDockerMCP adds Docker MCP configuration and persists it.
+func (c *Config) EnableDockerMCP() error {
+	if !IsDockerMCPAvailable() {
+		return fmt.Errorf("docker mcp is not available, please ensure docker is installed and 'docker mcp version' succeeds")
+	}
+
+	mcpConfig := MCPConfig{
+		Type:     MCPStdio,
+		Command:  "docker",
+		Args:     []string{"mcp", "gateway", "run"},
+		Disabled: false,
+	}
+
+	// Add to in-memory config.
+	if c.MCP == nil {
+		c.MCP = make(map[string]MCPConfig)
+	}
+	c.MCP[DockerMCPName] = mcpConfig
+
+	// Persist to config file.
+	if err := c.SetConfigField("mcp."+DockerMCPName, mcpConfig); err != nil {
+		return fmt.Errorf("failed to persist docker mcp configuration: %w", err)
+	}
+
+	return nil
+}
+
+// DisableDockerMCP removes Docker MCP configuration and persists the change.
+func (c *Config) DisableDockerMCP() error {
+	if c.MCP == nil {
+		return nil
+	}
+
+	// Remove from in-memory config.
+	delete(c.MCP, DockerMCPName)
+
+	// Persist to config file by setting to null.
+	if err := c.SetConfigField("mcp", c.MCP); err != nil {
+		return fmt.Errorf("failed to persist docker mcp removal: %w", err)
+	}
+
+	return nil
+}