feat: Phase 2 Workstream 3 — Go SDK (github.com/sentryagent/idp-sdk-go)

Single-package agentidp SDK in sdk-go/:
- AgentIdPClient composing AgentRegistryClient, CredentialClient,
  TokenServiceClient, AuditClient — all 14 endpoints covered
- Goroutine-safe TokenManager (sync.Mutex) with 60s refresh buffer
- AgentIdPError implementing error interface with Code/HTTPStatus/Details
- Context-aware: all service methods take context.Context as first arg
- doRequest shared helper; token endpoints use form-encoded POST directly
- go vet: 0 warnings | staticcheck: 0 warnings
- go test ./...: 37/37 passed | coverage: 81.0% (>80% gate)

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

sdk-go/agents_test.go

@@ -0,0 +1,181 @@
+package agentidp
+
+import (
+	"context"
+	"encoding/json"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+)
+
+// mockAgent is the canonical test agent fixture.
+var mockAgent = Agent{
+	AgentID:       "uuid-1",
+	Email:         "a@b.ai",
+	AgentType:     "screener",
+	Version:       "1.0.0",
+	Capabilities:  []string{"read"},
+	Owner:         "team",
+	DeploymentEnv: "production",
+	Status:        "active",
+	CreatedAt:     "2026-01-01T00:00:00Z",
+	UpdatedAt:     "2026-01-01T00:00:00Z",
+}
+
+var mockPaginatedAgents = PaginatedAgents{
+	Data:  []Agent{mockAgent},
+	Total: 1,
+	Page:  1,
+	Limit: 20,
+}
+
+// staticToken returns a fixed token for all test service clients.
+func staticToken(_ context.Context) (string, error) {
+	return "test-bearer-token", nil
+}
+
+func newAgentServer(t *testing.T, method, path string, status int, body interface{}) *httptest.Server {
+	t.Helper()
+	return httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if r.Method != method {
+			t.Errorf("expected method %s, got %s", method, r.Method)
+		}
+		if r.URL.Path != path {
+			t.Errorf("expected path %s, got %s", path, r.URL.Path)
+		}
+		if r.Header.Get("Authorization") == "" {
+			t.Error("missing Authorization header")
+		}
+		w.Header().Set("Content-Type", "application/json")
+		w.WriteHeader(status)
+		if body != nil {
+			_ = json.NewEncoder(w).Encode(body)
+		}
+	}))
+}
+
+func TestAgentRegistryClient_RegisterAgent(t *testing.T) {
+	srv := newAgentServer(t, http.MethodPost, "/api/v1/agents", 201, mockAgent)
+	defer srv.Close()
+
+	client := newAgentRegistryClient(srv.URL, staticToken, &http.Client{})
+	agent, err := client.RegisterAgent(context.Background(), RegisterAgentRequest{
+		Email: "a@b.ai", AgentType: "screener", Version: "1.0.0",
+		Capabilities: []string{"read"}, Owner: "team", DeploymentEnv: "production",
+	})
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if agent.AgentID != "uuid-1" {
+		t.Errorf("expected uuid-1, got %q", agent.AgentID)
+	}
+}
+
+func TestAgentRegistryClient_ListAgents(t *testing.T) {
+	srv := newAgentServer(t, http.MethodGet, "/api/v1/agents", 200, mockPaginatedAgents)
+	defer srv.Close()
+
+	client := newAgentRegistryClient(srv.URL, staticToken, &http.Client{})
+	result, err := client.ListAgents(context.Background(), nil)
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if result.Total != 1 {
+		t.Errorf("expected total 1, got %d", result.Total)
+	}
+	if len(result.Data) != 1 || result.Data[0].AgentID != "uuid-1" {
+		t.Error("unexpected data in paginated result")
+	}
+}
+
+func TestAgentRegistryClient_ListAgents_WithParams(t *testing.T) {
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if r.URL.Query().Get("status") != "active" {
+			t.Errorf("expected status=active, got %q", r.URL.Query().Get("status"))
+		}
+		w.Header().Set("Content-Type", "application/json")
+		_ = json.NewEncoder(w).Encode(mockPaginatedAgents)
+	}))
+	defer srv.Close()
+
+	client := newAgentRegistryClient(srv.URL, staticToken, &http.Client{})
+	_, err := client.ListAgents(context.Background(), &ListAgentsParams{Status: "active"})
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+}
+
+func TestAgentRegistryClient_GetAgent(t *testing.T) {
+	srv := newAgentServer(t, http.MethodGet, "/api/v1/agents/uuid-1", 200, mockAgent)
+	defer srv.Close()
+
+	client := newAgentRegistryClient(srv.URL, staticToken, &http.Client{})
+	agent, err := client.GetAgent(context.Background(), "uuid-1")
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if agent.AgentID != "uuid-1" {
+		t.Errorf("expected uuid-1, got %q", agent.AgentID)
+	}
+}
+
+func TestAgentRegistryClient_GetAgent_NotFound(t *testing.T) {
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.Header().Set("Content-Type", "application/json")
+		w.WriteHeader(404)
+		_ = json.NewEncoder(w).Encode(map[string]string{
+			"code":    "AgentNotFoundError",
+			"message": "Agent not found.",
+		})
+	}))
+	defer srv.Close()
+
+	client := newAgentRegistryClient(srv.URL, staticToken, &http.Client{})
+	_, err := client.GetAgent(context.Background(), "bad-id")
+	if err == nil {
+		t.Fatal("expected error, got nil")
+	}
+	apiErr, ok := err.(*AgentIdPError)
+	if !ok {
+		t.Fatalf("expected *AgentIdPError, got %T", err)
+	}
+	if apiErr.Code != "AgentNotFoundError" {
+		t.Errorf("expected AgentNotFoundError, got %q", apiErr.Code)
+	}
+	if apiErr.HTTPStatus != 404 {
+		t.Errorf("expected 404, got %d", apiErr.HTTPStatus)
+	}
+}
+
+func TestAgentRegistryClient_UpdateAgent(t *testing.T) {
+	updated := mockAgent
+	updated.Version = "2.0.0"
+	srv := newAgentServer(t, http.MethodPatch, "/api/v1/agents/uuid-1", 200, updated)
+	defer srv.Close()
+
+	v := "2.0.0"
+	client := newAgentRegistryClient(srv.URL, staticToken, &http.Client{})
+	agent, err := client.UpdateAgent(context.Background(), "uuid-1", UpdateAgentRequest{Version: &v})
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if agent.Version != "2.0.0" {
+		t.Errorf("expected version 2.0.0, got %q", agent.Version)
+	}
+}
+
+func TestAgentRegistryClient_DecommissionAgent(t *testing.T) {
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if r.Method != http.MethodDelete {
+			t.Errorf("expected DELETE, got %s", r.Method)
+		}
+		w.WriteHeader(204)
+	}))
+	defer srv.Close()
+
+	client := newAgentRegistryClient(srv.URL, staticToken, &http.Client{})
+	err := client.DecommissionAgent(context.Background(), "uuid-1")
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+}