diff --git a/cmd/root/new.go b/cmd/root/new.go
index af17d6caf..189684795 100644
--- a/cmd/root/new.go
+++ b/cmd/root/new.go
@@ -63,7 +63,7 @@ func (f *newFlags) runNewCommand(cmd *cobra.Command, args []string) error {
 	}
 	if len(args) > 0 {
 		arg := strings.Join(args, " ")
-		opts = append(opts, session.WithUserMessage("", arg))
+		opts = append(opts, session.WithUserMessage(arg))
 		firstMessage = &arg
 	}
 
diff --git a/e2e/cagent_mcp_test.go b/e2e/cagent_mcp_test.go
index affa73ed0..ecc5ffe02 100644
--- a/e2e/cagent_mcp_test.go
+++ b/e2e/cagent_mcp_test.go
@@ -22,7 +22,7 @@ func TestMCP_SingleAgent(t *testing.T) {
 		require.NoError(t, team.StopToolSets(ctx))
 	})
 
-	handler := mcp.CreateToolHandler(team, "root", "testdata/basic.yaml")
+	handler := mcp.CreateToolHandler(team, "root")
 	_, output, err := handler(ctx, nil, mcp.ToolInput{
 		Message: "What is 2+2? Answer in one sentence.",
 	})
@@ -43,7 +43,7 @@ func TestMCP_MultiAgent(t *testing.T) {
 		require.NoError(t, team.StopToolSets(ctx))
 	})
 
-	handler := mcp.CreateToolHandler(team, "web", "testdata/multi.yaml")
+	handler := mcp.CreateToolHandler(team, "web")
 	_, output, err := handler(ctx, nil, mcp.ToolInput{
 		Message: "Say hello in one sentence.",
 	})
diff --git a/e2e/runtime_test.go b/e2e/runtime_test.go
index af70a6e60..2524ccc18 100644
--- a/e2e/runtime_test.go
+++ b/e2e/runtime_test.go
@@ -23,7 +23,7 @@ func TestRuntime_OpenAI_Basic(t *testing.T) {
 	rt, err := runtime.New(team)
 	require.NoError(t, err)
 
-	sess := session.New(session.WithUserMessage("", "What's 2+2?"))
+	sess := session.New(session.WithUserMessage("What's 2+2?"))
 	_, err = rt.Run(ctx, sess)
 	require.NoError(t, err)
 
@@ -44,7 +44,7 @@ func TestRuntime_Mistral_Basic(t *testing.T) {
 	rt, err := runtime.New(team)
 	require.NoError(t, err)
 
-	sess := session.New(session.WithUserMessage("", "What's 2+2?"))
+	sess := session.New(session.WithUserMessage("What's 2+2?"))
 	_, err = rt.Run(ctx, sess)
 	require.NoError(t, err)
 
diff --git a/examples/golibrary/builtintool/main.go b/examples/golibrary/builtintool/main.go
index d547db885..f0583598f 100644
--- a/examples/golibrary/builtintool/main.go
+++ b/examples/golibrary/builtintool/main.go
@@ -56,7 +56,7 @@ func run(ctx context.Context) error {
 		return err
 	}
 
-	sess := session.New(session.WithUserMessage("", "Tell me a story about my current directory"))
+	sess := session.New(session.WithUserMessage("Tell me a story about my current directory"))
 
 	messages, err := rt.Run(ctx, sess)
 	if err != nil {
diff --git a/examples/golibrary/multi/main.go b/examples/golibrary/multi/main.go
index 08196ec96..63dffb390 100644
--- a/examples/golibrary/multi/main.go
+++ b/examples/golibrary/multi/main.go
@@ -56,7 +56,7 @@ func run(ctx context.Context) error {
 		return err
 	}
 
-	sess := session.New(session.WithUserMessage("", "Ask your child how they are doing and tell me what they said"))
+	sess := session.New(session.WithUserMessage("Ask your child how they are doing and tell me what they said"))
 
 	messages, err := rt.Run(ctx, sess)
 	if err != nil {
diff --git a/examples/golibrary/simple/main.go b/examples/golibrary/simple/main.go
index 8608325cd..9561e9c83 100644
--- a/examples/golibrary/simple/main.go
+++ b/examples/golibrary/simple/main.go
@@ -52,7 +52,7 @@ func run(ctx context.Context) error {
 		return err
 	}
 
-	sess := session.New(session.WithUserMessage("", "How are you doing?"))
+	sess := session.New(session.WithUserMessage("How are you doing?"))
 
 	messages, err := rt.Run(ctx, sess)
 	if err != nil {
diff --git a/examples/golibrary/stream/main.go b/examples/golibrary/stream/main.go
index 1d54d26a3..059a24bb6 100644
--- a/examples/golibrary/stream/main.go
+++ b/examples/golibrary/stream/main.go
@@ -51,7 +51,7 @@ func run(ctx context.Context) error {
 		return err
 	}
 
-	sess := session.New(session.WithUserMessage("", "How are you doing?"))
+	sess := session.New(session.WithUserMessage("How are you doing?"))
 
 	events := rt.RunStream(ctx, sess)
 	for event := range events {
diff --git a/examples/golibrary/tool/main.go b/examples/golibrary/tool/main.go
index 2ffa2a86f..96b211fbd 100644
--- a/examples/golibrary/tool/main.go
+++ b/examples/golibrary/tool/main.go
@@ -80,7 +80,7 @@ func run(ctx context.Context) error {
 		return err
 	}
 
-	sess := session.New(session.WithUserMessage("", "What is 1 + 2?"))
+	sess := session.New(session.WithUserMessage("What is 1 + 2?"))
 
 	messages, err := rt.Run(ctx, sess)
 	if err != nil {
diff --git a/pkg/a2a/adapter.go b/pkg/a2a/adapter.go
index 3b4868d62..8fd7c15a2 100644
--- a/pkg/a2a/adapter.go
+++ b/pkg/a2a/adapter.go
@@ -46,7 +46,7 @@ func runCAgent(ctx agent.InvocationContext, t *team.Team, agentName string, a *c
 
 		// Create a cagent session
 		sess := session.New(
-			session.WithUserMessage("", message),
+			session.WithUserMessage(message),
 			session.WithMaxIterations(a.MaxIterations()),
 			session.WithToolsApproved(true),
 		)
diff --git a/pkg/a2a/server.go b/pkg/a2a/server.go
index 0efddb48d..2882ab5b2 100644
--- a/pkg/a2a/server.go
+++ b/pkg/a2a/server.go
@@ -23,7 +23,7 @@ import (
 )
 
 func Start(ctx context.Context, out *cli.Printer, agentFilename, agentName string, runConfig *config.RuntimeConfig, ln net.Listener) error {
-	slog.Debug("Starting A2A server", "agent", agentFilename, "addr", ln.Addr().String())
+	slog.Debug("Starting A2A server", "agent", agentName, "addr", ln.Addr().String())
 
 	t, err := teamloader.Load(ctx, agentFilename, runConfig)
 	if err != nil {
diff --git a/pkg/acp/agent.go b/pkg/acp/agent.go
index 8c5db9120..5b43e8b9e 100644
--- a/pkg/acp/agent.go
+++ b/pkg/acp/agent.go
@@ -69,7 +69,6 @@ func (a *Agent) Initialize(ctx context.Context, params acp.InitializeRequest) (a
 
 	a.mu.Lock()
 	defer a.mu.Unlock()
-	slog.Debug("Loading teams", "agent_file", a.agentFilename)
 	t, err := teamloader.Load(ctx, a.agentFilename, a.runtimeConfig, teamloader.WithToolsetRegistry(createToolsetRegistry(a)))
 	if err != nil {
 		return acp.InitializeResponse{}, fmt.Errorf("failed to load teams: %w", err)
diff --git a/pkg/app/transcript_test.go b/pkg/app/transcript_test.go
index 3b5608f75..22092e404 100644
--- a/pkg/app/transcript_test.go
+++ b/pkg/app/transcript_test.go
@@ -11,14 +11,14 @@ import (
 )
 
 func TestSimple(t *testing.T) {
-	sess := session.New(session.WithUserMessage("", "Hello"))
+	sess := session.New(session.WithUserMessage("Hello"))
 	content := transcript(sess)
 	golden.Assert(t, content, "simple.golden")
 }
 
 func TestAssistantMessage(t *testing.T) {
 	sess := session.New(
-		session.WithUserMessage("", "Hello"),
+		session.WithUserMessage("Hello"),
 	)
 	sess.AddMessage(&session.Message{
 		AgentName: "root",
@@ -33,7 +33,7 @@ func TestAssistantMessage(t *testing.T) {
 
 func TestAssistantMessageWithReasoning(t *testing.T) {
 	sess := session.New(
-		session.WithUserMessage("", "Hello"),
+		session.WithUserMessage("Hello"),
 	)
 	sess.AddMessage(&session.Message{
 		AgentName: "root",
@@ -49,7 +49,7 @@ func TestAssistantMessageWithReasoning(t *testing.T) {
 
 func TestToolCalls(t *testing.T) {
 	sess := session.New(
-		session.WithUserMessage("", "Hello"),
+		session.WithUserMessage("Hello"),
 	)
 	sess.AddMessage(&session.Message{
 		AgentName: "root",
diff --git a/pkg/creator/agent.go b/pkg/creator/agent.go
index c0b695959..919f73780 100644
--- a/pkg/creator/agent.go
+++ b/pkg/creator/agent.go
@@ -114,7 +114,7 @@ func CreateAgent(ctx context.Context, baseDir, prompt string, runConfig *config.
 	}
 
 	sess := session.New(
-		session.WithUserMessage("", prompt),
+		session.WithUserMessage(prompt),
 		session.WithToolsApproved(true),
 	)
 
diff --git a/pkg/mcp/server.go b/pkg/mcp/server.go
index 2f3f9da3e..be9c29a92 100644
--- a/pkg/mcp/server.go
+++ b/pkg/mcp/server.go
@@ -8,7 +8,6 @@ import (
 	"github.com/modelcontextprotocol/go-sdk/mcp"
 
 	"github.com/docker/cagent/pkg/agent"
-	"github.com/docker/cagent/pkg/agentfile"
 	"github.com/docker/cagent/pkg/cli"
 	"github.com/docker/cagent/pkg/config"
 	"github.com/docker/cagent/pkg/runtime"
@@ -30,11 +29,6 @@ type ToolOutput struct {
 func StartMCPServer(ctx context.Context, out *cli.Printer, agentFilename string, runConfig *config.RuntimeConfig) error {
 	slog.Debug("Starting MCP server", "agent", agentFilename)
 
-	agentFilename, err := agentfile.Resolve(ctx, out, agentFilename)
-	if err != nil {
-		return err
-	}
-
 	t, err := teamloader.Load(ctx, agentFilename, runConfig)
 	if err != nil {
 		return fmt.Errorf("failed to load agents: %w", err)
@@ -82,7 +76,7 @@ func StartMCPServer(ctx context.Context, out *cli.Printer, agentFilename string,
 			OutputSchema: tools.MustSchemaFor[ToolOutput](),
 		}
 
-		mcp.AddTool(server, toolDef, CreateToolHandler(t, agentName, agentFilename))
+		mcp.AddTool(server, toolDef, CreateToolHandler(t, agentName))
 	}
 
 	slog.Debug("MCP server starting with stdio transport")
@@ -94,7 +88,7 @@ func StartMCPServer(ctx context.Context, out *cli.Printer, agentFilename string,
 	return nil
 }
 
-func CreateToolHandler(t *team.Team, agentName, agentFilename string) func(context.Context, *mcp.CallToolRequest, ToolInput) (*mcp.CallToolResult, ToolOutput, error) {
+func CreateToolHandler(t *team.Team, agentName string) func(context.Context, *mcp.CallToolRequest, ToolInput) (*mcp.CallToolResult, ToolOutput, error) {
 	return func(ctx context.Context, req *mcp.CallToolRequest, input ToolInput) (*mcp.CallToolResult, ToolOutput, error) {
 		slog.Debug("MCP tool called", "agent", agentName, "message", input.Message)
 
@@ -106,7 +100,7 @@ func CreateToolHandler(t *team.Team, agentName, agentFilename string) func(conte
 		sess := session.New(
 			session.WithTitle("MCP tool call"),
 			session.WithMaxIterations(ag.MaxIterations()),
-			session.WithUserMessage(agentFilename, input.Message),
+			session.WithUserMessage(input.Message),
 			session.WithToolsApproved(true),
 		)
 
diff --git a/pkg/oci/build.go b/pkg/oci/build.go
index 1607ae1b8..45dde6579 100644
--- a/pkg/oci/build.go
+++ b/pkg/oci/build.go
@@ -28,8 +28,8 @@ type Options struct {
 	Pull    bool
 }
 
-func BuildDockerImage(ctx context.Context, out *cli.Printer, agentFilePath string, fs filesystem.FS, dockerImageName string, opts Options) error {
-	cfg, err := config.LoadConfig(ctx, agentFilePath, fs)
+func BuildDockerImage(ctx context.Context, out *cli.Printer, agentFilename string, fs filesystem.FS, dockerImageName string, opts Options) error {
+	cfg, err := config.LoadConfig(ctx, agentFilename, fs)
 	if err != nil {
 		return err
 	}
diff --git a/pkg/runtime/runtime.go b/pkg/runtime/runtime.go
index 0991a393d..73420e59e 100644
--- a/pkg/runtime/runtime.go
+++ b/pkg/runtime/runtime.go
@@ -1424,7 +1424,7 @@ func (r *LocalRuntime) generateSessionTitle(ctx context.Context, sess *session.S
 		team.WithAgents(agent.New("root", systemPrompt, agent.WithModel(titleModel))),
 	)
 	titleSession := session.New(
-		session.WithUserMessage("", userPrompt),
+		session.WithUserMessage(userPrompt),
 		session.WithTitle("Generating title..."),
 	)
 
diff --git a/pkg/runtime/runtime_response_api_test.go b/pkg/runtime/runtime_response_api_test.go
index 26184a983..0df7fdbd2 100644
--- a/pkg/runtime/runtime_response_api_test.go
+++ b/pkg/runtime/runtime_response_api_test.go
@@ -22,7 +22,7 @@ func TestResponseAPIToolCallHandling(t *testing.T) {
 		AddStopWithUsage(10, 15).
 		Build()
 
-	sess := session.New(session.WithUserMessage("", "Search for test"))
+	sess := session.New(session.WithUserMessage("Search for test"))
 
 	events := runSession(t, sess, stream)
 
@@ -55,7 +55,7 @@ func TestResponseAPIMultipleToolCalls(t *testing.T) {
 		AddStopWithUsage(20, 30).
 		Build()
 
-	sess := session.New(session.WithUserMessage("", "Search and calculate"))
+	sess := session.New(session.WithUserMessage("Search and calculate"))
 
 	events := runSession(t, sess, stream)
 
diff --git a/pkg/runtime/runtime_test.go b/pkg/runtime/runtime_test.go
index 746653b18..078d484af 100644
--- a/pkg/runtime/runtime_test.go
+++ b/pkg/runtime/runtime_test.go
@@ -212,7 +212,7 @@ func TestSimple(t *testing.T) {
 		AddStopWithUsage(3, 2).
 		Build()
 
-	sess := session.New(session.WithUserMessage("", "Hi"))
+	sess := session.New(session.WithUserMessage("Hi"))
 
 	events := runSession(t, sess, stream)
 
@@ -240,7 +240,7 @@ func TestMultipleContentChunks(t *testing.T) {
 		AddStopWithUsage(8, 12).
 		Build()
 
-	sess := session.New(session.WithUserMessage("", "Please greet me"))
+	sess := session.New(session.WithUserMessage("Please greet me"))
 
 	events := runSession(t, sess, stream)
 
@@ -270,7 +270,7 @@ func TestWithReasoning(t *testing.T) {
 		AddStopWithUsage(10, 15).
 		Build()
 
-	sess := session.New(session.WithUserMessage("", "Hi"))
+	sess := session.New(session.WithUserMessage("Hi"))
 
 	events := runSession(t, sess, stream)
 
@@ -299,7 +299,7 @@ func TestMixedContentAndReasoning(t *testing.T) {
 		AddStopWithUsage(15, 20).
 		Build()
 
-	sess := session.New(session.WithUserMessage("", "Hi there"))
+	sess := session.New(session.WithUserMessage("Hi there"))
 
 	events := runSession(t, sess, stream)
 
@@ -327,7 +327,7 @@ func TestToolCallSequence(t *testing.T) {
 		AddStopWithUsage(5, 8).
 		Build()
 
-	sess := session.New(session.WithUserMessage("", "Please use the test tool"))
+	sess := session.New(session.WithUserMessage("Please use the test tool"))
 
 	events := runSession(t, sess, stream)
 
@@ -346,7 +346,7 @@ func TestErrorEvent(t *testing.T) {
 	rt, err := New(tm, WithSessionCompaction(false), WithModelStore(mockModelStore{}))
 	require.NoError(t, err)
 
-	sess := session.New(session.WithUserMessage("", "Hi"))
+	sess := session.New(session.WithUserMessage("Hi"))
 	sess.Title = "Unit Test"
 
 	evCh := rt.RunStream(t.Context(), sess)
@@ -382,7 +382,7 @@ func TestContextCancellation(t *testing.T) {
 	rt, err := New(tm, WithSessionCompaction(false), WithModelStore(mockModelStore{}))
 	require.NoError(t, err)
 
-	sess := session.New(session.WithUserMessage("", "Hi"))
+	sess := session.New(session.WithUserMessage("Hi"))
 	sess.Title = "Unit Test"
 
 	ctx, cancel := context.WithCancel(t.Context())
@@ -547,7 +547,7 @@ func TestToolCallVariations(t *testing.T) {
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
 			stream := tt.streamBuilder().Build()
-			sess := session.New(session.WithUserMessage("", "Use tools"))
+			sess := session.New(session.WithUserMessage("Use tools"))
 			events := runSession(t, sess, stream)
 
 			require.True(t, hasEventType(t, events, &PartialToolCallEvent{}), "Expected PartialToolCallEvent for %s", tt.description)
@@ -621,7 +621,7 @@ func TestCompactionOccursAfterToolResultsWhenToolUsePresent(t *testing.T) {
 	rt, err := New(tm, WithSessionCompaction(true), WithModelStore(mockModelStoreWithLimit{limit: 100}))
 	require.NoError(t, err)
 
-	sess := session.New(session.WithUserMessage("", "Start"))
+	sess := session.New(session.WithUserMessage("Start"))
 	events := rt.RunStream(t.Context(), sess)
 
 	// Collect events
@@ -801,7 +801,7 @@ func TestProcessToolCalls_UnknownTool_NoToolResultMessage(t *testing.T) {
 	// Register default tools (contains only transfer_task) to ensure unknown tool isn't matched
 	rt.registerDefaultTools()
 
-	sess := session.New(session.WithUserMessage("", "Start"))
+	sess := session.New(session.WithUserMessage("Start"))
 
 	// Simulate a model-issued tool call to a non-existent tool
 	calls := []tools.ToolCall{{
diff --git a/pkg/session/session.go b/pkg/session/session.go
index 651a1506c..b5affcc1e 100644
--- a/pkg/session/session.go
+++ b/pkg/session/session.go
@@ -209,9 +209,9 @@ func (s *Session) GetLastUserMessageContent() string {
 
 type Opt func(s *Session)
 
-func WithUserMessage(agentFilename, content string) Opt {
+func WithUserMessage(content string) Opt {
 	return func(s *Session) {
-		s.AddMessage(UserMessage(agentFilename, content))
+		s.AddMessage(UserMessage("", content))
 	}
 }
 
diff --git a/pkg/teamloader/teamloader.go b/pkg/teamloader/teamloader.go
index 953591fc1..93b0c1783 100644
--- a/pkg/teamloader/teamloader.go
+++ b/pkg/teamloader/teamloader.go
@@ -107,8 +107,8 @@ func WithID(id string) Opt {
 
 // Load loads an agent team from the given file path.
 // Prefers LoadFrom for more control over the source.
-func Load(ctx context.Context, p string, runtimeConfig *config.RuntimeConfig, opts ...Opt) (*team.Team, error) {
-	return LoadFrom(ctx, NewFileSource(p), runtimeConfig, opts...)
+func Load(ctx context.Context, agentFilename string, runtimeConfig *config.RuntimeConfig, opts ...Opt) (*team.Team, error) {
+	return LoadFrom(ctx, NewFileSource(agentFilename), runtimeConfig, opts...)
 }
 
 // LoadFrom loads an agent team from the given source