diff --git a/pkg/agentic/plan_logic_test.go b/pkg/agentic/plan_logic_test.go
new file mode 100644
index 0000000..fe6179b
--- /dev/null
+++ b/pkg/agentic/plan_logic_test.go
@@ -0,0 +1,175 @@
+// SPDX-License-Identifier: EUPL-1.2
+
+package agentic
+
+import (
+	"path/filepath"
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+// --- planPath ---
+
+func TestPlanPath_Good_BasicFormat(t *testing.T) {
+	result := planPath("/tmp/plans", "my-plan-abc123")
+	assert.Equal(t, "/tmp/plans/my-plan-abc123.json", result)
+}
+
+func TestPlanPath_Good_NestedIDStripped(t *testing.T) {
+	// PathBase strips directory component — prevents path traversal
+	result := planPath("/plans", "../../../etc/passwd")
+	assert.Equal(t, "/plans/passwd.json", result)
+}
+
+func TestPlanPath_Good_SimpleID(t *testing.T) {
+	assert.Equal(t, "/data/test.json", planPath("/data", "test"))
+}
+
+func TestPlanPath_Good_SlugWithDashes(t *testing.T) {
+	assert.Equal(t, "/root/migrate-core-abc123.json", planPath("/root", "migrate-core-abc123"))
+}
+
+func TestPlanPath_Bad_DotID(t *testing.T) {
+	// "." is sanitised to "invalid" to prevent exploiting the root directory
+	result := planPath("/plans", ".")
+	assert.Equal(t, "/plans/invalid.json", result)
+}
+
+func TestPlanPath_Bad_DoubleDotID(t *testing.T) {
+	result := planPath("/plans", "..")
+	assert.Equal(t, "/plans/invalid.json", result)
+}
+
+func TestPlanPath_Bad_EmptyID(t *testing.T) {
+	result := planPath("/plans", "")
+	assert.Equal(t, "/plans/invalid.json", result)
+}
+
+// --- readPlan / writePlan ---
+
+func TestReadWritePlan_Good_BasicRoundtrip(t *testing.T) {
+	dir := t.TempDir()
+	now := time.Now().Truncate(time.Second)
+
+	plan := &Plan{
+		ID:        "basic-plan-abc",
+		Title:     "Basic Plan",
+		Status:    "draft",
+		Repo:      "go-io",
+		Org:       "core",
+		Objective: "Verify round-trip works",
+		Agent:     "claude:opus",
+		CreatedAt: now,
+		UpdatedAt: now,
+	}
+
+	path, err := writePlan(dir, plan)
+	require.NoError(t, err)
+	assert.Equal(t, filepath.Join(dir, "basic-plan-abc.json"), path)
+
+	read, err := readPlan(dir, "basic-plan-abc")
+	require.NoError(t, err)
+
+	assert.Equal(t, plan.ID, read.ID)
+	assert.Equal(t, plan.Title, read.Title)
+	assert.Equal(t, plan.Status, read.Status)
+	assert.Equal(t, plan.Repo, read.Repo)
+	assert.Equal(t, plan.Org, read.Org)
+	assert.Equal(t, plan.Objective, read.Objective)
+	assert.Equal(t, plan.Agent, read.Agent)
+}
+
+func TestReadWritePlan_Good_WithPhases(t *testing.T) {
+	dir := t.TempDir()
+
+	plan := &Plan{
+		ID:        "phase-plan-abc",
+		Title:     "Phased Work",
+		Status:    "in_progress",
+		Objective: "Multi-phase plan",
+		Phases: []Phase{
+			{Number: 1, Name: "Setup", Status: "done", Criteria: []string{"repo cloned", "deps installed"}, Tests: 3},
+			{Number: 2, Name: "Implement", Status: "in_progress", Notes: "WIP"},
+			{Number: 3, Name: "Verify", Status: "pending"},
+		},
+	}
+
+	_, err := writePlan(dir, plan)
+	require.NoError(t, err)
+
+	read, err := readPlan(dir, "phase-plan-abc")
+	require.NoError(t, err)
+
+	require.Len(t, read.Phases, 3)
+	assert.Equal(t, "Setup", read.Phases[0].Name)
+	assert.Equal(t, "done", read.Phases[0].Status)
+	assert.Equal(t, []string{"repo cloned", "deps installed"}, read.Phases[0].Criteria)
+	assert.Equal(t, 3, read.Phases[0].Tests)
+	assert.Equal(t, "WIP", read.Phases[1].Notes)
+	assert.Equal(t, "pending", read.Phases[2].Status)
+}
+
+func TestReadPlan_Bad_MissingFile(t *testing.T) {
+	dir := t.TempDir()
+	_, err := readPlan(dir, "nonexistent-plan")
+	assert.Error(t, err)
+}
+
+func TestReadPlan_Bad_CorruptJSON(t *testing.T) {
+	dir := t.TempDir()
+	require.True(t, fs.Write(filepath.Join(dir, "bad.json"), `{broken`).OK)
+
+	_, err := readPlan(dir, "bad")
+	assert.Error(t, err)
+}
+
+func TestWritePlan_Good_CreatesNestedDir(t *testing.T) {
+	base := t.TempDir()
+	nested := filepath.Join(base, "deep", "nested", "plans")
+
+	plan := &Plan{
+		ID:        "deep-plan-xyz",
+		Title:     "Deep",
+		Status:    "draft",
+		Objective: "Test nested dir creation",
+	}
+
+	path, err := writePlan(nested, plan)
+	require.NoError(t, err)
+	assert.Equal(t, filepath.Join(nested, "deep-plan-xyz.json"), path)
+	assert.True(t, fs.IsFile(path))
+}
+
+func TestWritePlan_Good_OverwriteExistingLogic(t *testing.T) {
+	dir := t.TempDir()
+
+	plan := &Plan{
+		ID:        "overwrite-plan-abc",
+		Title:     "First Title",
+		Status:    "draft",
+		Objective: "Initial",
+	}
+	_, err := writePlan(dir, plan)
+	require.NoError(t, err)
+
+	plan.Title = "Second Title"
+	plan.Status = "approved"
+	_, err = writePlan(dir, plan)
+	require.NoError(t, err)
+
+	read, err := readPlan(dir, "overwrite-plan-abc")
+	require.NoError(t, err)
+	assert.Equal(t, "Second Title", read.Title)
+	assert.Equal(t, "approved", read.Status)
+}
+
+func TestReadPlan_Ugly_EmptyFileLogic(t *testing.T) {
+	dir := t.TempDir()
+	require.True(t, fs.Write(filepath.Join(dir, "empty.json"), "").OK)
+
+	_, err := readPlan(dir, "empty")
+	assert.Error(t, err)
+}
diff --git a/pkg/agentic/queue_logic_test.go b/pkg/agentic/queue_logic_test.go
new file mode 100644
index 0000000..c6ce08b
--- /dev/null
+++ b/pkg/agentic/queue_logic_test.go
@@ -0,0 +1,220 @@
+// SPDX-License-Identifier: EUPL-1.2
+
+package agentic
+
+import (
+	"os/exec"
+	"path/filepath"
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+// --- countRunningByModel ---
+
+func TestCountRunningByModel_Good_Empty(t *testing.T) {
+	root := t.TempDir()
+	t.Setenv("CORE_WORKSPACE", root)
+
+	s := &PrepSubsystem{}
+	assert.Equal(t, 0, s.countRunningByModel("claude:opus"))
+}
+
+func TestCountRunningByModel_Good_SkipsNonRunning(t *testing.T) {
+	root := t.TempDir()
+	t.Setenv("CORE_WORKSPACE", root)
+
+	// Completed workspace — must not be counted
+	ws := filepath.Join(root, "workspace", "test-ws")
+	require.True(t, fs.EnsureDir(ws).OK)
+	require.NoError(t, writeStatus(ws, &WorkspaceStatus{
+		Status: "completed",
+		Agent:  "codex:gpt-5.4",
+		PID:    0,
+	}))
+
+	s := &PrepSubsystem{}
+	assert.Equal(t, 0, s.countRunningByModel("codex:gpt-5.4"))
+}
+
+func TestCountRunningByModel_Good_SkipsMismatchedModel(t *testing.T) {
+	root := t.TempDir()
+	t.Setenv("CORE_WORKSPACE", root)
+
+	ws := filepath.Join(root, "workspace", "model-ws")
+	require.True(t, fs.EnsureDir(ws).OK)
+	require.NoError(t, writeStatus(ws, &WorkspaceStatus{
+		Status: "running",
+		Agent:  "gemini:flash",
+		PID:    0,
+	}))
+
+	s := &PrepSubsystem{}
+	// Asking for gemini:pro — must not count gemini:flash
+	assert.Equal(t, 0, s.countRunningByModel("gemini:pro"))
+}
+
+func TestCountRunningByModel_Good_DeepLayout(t *testing.T) {
+	root := t.TempDir()
+	t.Setenv("CORE_WORKSPACE", root)
+
+	// Deep layout: workspace/org/repo/task-N/status.json
+	ws := filepath.Join(root, "workspace", "core", "go-io", "task-1")
+	require.True(t, fs.EnsureDir(ws).OK)
+	require.NoError(t, writeStatus(ws, &WorkspaceStatus{
+		Status: "completed",
+		Agent:  "codex:gpt-5.4",
+	}))
+
+	s := &PrepSubsystem{}
+	// Completed, so count is still 0
+	assert.Equal(t, 0, s.countRunningByModel("codex:gpt-5.4"))
+}
+
+// --- drainQueue ---
+
+func TestDrainQueue_Good_FrozenReturnsImmediately(t *testing.T) {
+	root := t.TempDir()
+	t.Setenv("CORE_WORKSPACE", root)
+
+	s := &PrepSubsystem{frozen: true, backoff: make(map[string]time.Time), failCount: make(map[string]int)}
+	// Must not panic and must not block
+	assert.NotPanics(t, func() {
+		s.drainQueue()
+	})
+}
+
+func TestDrainQueue_Good_EmptyWorkspace(t *testing.T) {
+	root := t.TempDir()
+	t.Setenv("CORE_WORKSPACE", root)
+
+	s := &PrepSubsystem{frozen: false, backoff: make(map[string]time.Time), failCount: make(map[string]int)}
+	// No workspaces — must return without error/panic
+	assert.NotPanics(t, func() {
+		s.drainQueue()
+	})
+}
+
+// --- Poke ---
+
+func TestPoke_Good_NilChannel(t *testing.T) {
+	s := &PrepSubsystem{pokeCh: nil}
+	// Must not panic when pokeCh is nil
+	assert.NotPanics(t, func() {
+		s.Poke()
+	})
+}
+
+func TestPoke_Good_ChannelReceivesSignal(t *testing.T) {
+	s := &PrepSubsystem{}
+	s.pokeCh = make(chan struct{}, 1)
+
+	s.Poke()
+	assert.Len(t, s.pokeCh, 1, "poke should enqueue one signal")
+}
+
+func TestPoke_Good_NonBlockingWhenFull(t *testing.T) {
+	s := &PrepSubsystem{}
+	s.pokeCh = make(chan struct{}, 1)
+	// Pre-fill the channel
+	s.pokeCh <- struct{}{}
+
+	// Second poke must not block or panic
+	assert.NotPanics(t, func() {
+		s.Poke()
+	})
+	assert.Len(t, s.pokeCh, 1, "channel length should remain 1")
+}
+
+// --- StartRunner ---
+
+func TestStartRunner_Good_CreatesPokeCh(t *testing.T) {
+	root := t.TempDir()
+	t.Setenv("CORE_WORKSPACE", root)
+	t.Setenv("CORE_AGENT_DISPATCH", "")
+
+	s := NewPrep()
+	assert.Nil(t, s.pokeCh)
+
+	s.StartRunner()
+	assert.NotNil(t, s.pokeCh, "StartRunner should initialise pokeCh")
+}
+
+func TestStartRunner_Good_FrozenByDefault(t *testing.T) {
+	root := t.TempDir()
+	t.Setenv("CORE_WORKSPACE", root)
+	t.Setenv("CORE_AGENT_DISPATCH", "")
+
+	s := NewPrep()
+	s.StartRunner()
+	assert.True(t, s.frozen, "queue should be frozen by default")
+}
+
+func TestStartRunner_Good_AutoStartEnvVar(t *testing.T) {
+	root := t.TempDir()
+	t.Setenv("CORE_WORKSPACE", root)
+	t.Setenv("CORE_AGENT_DISPATCH", "1")
+
+	s := NewPrep()
+	s.StartRunner()
+	assert.False(t, s.frozen, "CORE_AGENT_DISPATCH=1 should unfreeze the queue")
+}
+
+// --- DefaultBranch ---
+
+func TestDefaultBranch_Good_DefaultsToMain(t *testing.T) {
+	// Non-git temp dir — git commands fail, fallback is "main"
+	dir := t.TempDir()
+	branch := DefaultBranch(dir)
+	assert.Equal(t, "main", branch)
+}
+
+func TestDefaultBranch_Good_RealGitRepo(t *testing.T) {
+	dir := t.TempDir()
+	// Init a real git repo with a main branch
+	require.NoError(t, runGitInit(dir))
+
+	branch := DefaultBranch(dir)
+	// Any valid branch name — just must not panic or be empty
+	assert.NotEmpty(t, branch)
+}
+
+// --- LocalFs ---
+
+func TestLocalFs_Good_NonNil(t *testing.T) {
+	f := LocalFs()
+	assert.NotNil(t, f, "LocalFs should return a non-nil *core.Fs")
+}
+
+func TestLocalFs_Good_CanRead(t *testing.T) {
+	dir := t.TempDir()
+	path := filepath.Join(dir, "hello.txt")
+	require.True(t, fs.Write(path, "hello").OK)
+
+	f := LocalFs()
+	r := f.Read(path)
+	assert.True(t, r.OK)
+	assert.Equal(t, "hello", r.Value.(string))
+}
+
+// --- helpers ---
+
+// runGitInit initialises a bare git repo with one commit so branch detection works.
+func runGitInit(dir string) error {
+	cmds := [][]string{
+		{"git", "init", "-b", "main"},
+		{"git", "config", "user.email", "test@test.com"},
+		{"git", "config", "user.name", "Test"},
+		{"git", "commit", "--allow-empty", "-m", "init"},
+	}
+	for _, args := range cmds {
+		cmd := exec.Command(args[0], args[1:]...)
+		cmd.Dir = dir
+		if err := cmd.Run(); err != nil {
+			return err
+		}
+	}
+	return nil
+}
diff --git a/pkg/agentic/register_test.go b/pkg/agentic/register_test.go
new file mode 100644
index 0000000..ce06b1d
--- /dev/null
+++ b/pkg/agentic/register_test.go
@@ -0,0 +1,131 @@
+// SPDX-License-Identifier: EUPL-1.2
+
+package agentic
+
+import (
+	"context"
+	"testing"
+
+	core "dappco.re/go/core"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+// --- Register ---
+
+func TestRegister_Good_ServiceRegistered(t *testing.T) {
+	t.Setenv("CORE_WORKSPACE", t.TempDir())
+	t.Setenv("FORGE_TOKEN", "")
+	t.Setenv("FORGE_URL", "")
+	t.Setenv("CORE_BRAIN_KEY", "")
+	t.Setenv("CORE_BRAIN_URL", "")
+
+	c := core.New(core.WithService(Register))
+	require.NotNil(t, c)
+
+	// Service auto-registered under the last segment of the package path: "agentic"
+	prep, ok := core.ServiceFor[*PrepSubsystem](c, "agentic")
+	assert.True(t, ok, "PrepSubsystem must be registered as \"agentic\"")
+	assert.NotNil(t, prep)
+}
+
+func TestRegister_Good_CoreWired(t *testing.T) {
+	t.Setenv("CORE_WORKSPACE", t.TempDir())
+	t.Setenv("FORGE_TOKEN", "")
+	t.Setenv("FORGE_URL", "")
+
+	c := core.New(core.WithService(Register))
+
+	prep, ok := core.ServiceFor[*PrepSubsystem](c, "agentic")
+	require.True(t, ok)
+	// Register must wire s.core — service needs it for config access
+	assert.NotNil(t, prep.core, "Register must set prep.core")
+	assert.Equal(t, c, prep.core)
+}
+
+func TestRegister_Good_AgentsConfigLoaded(t *testing.T) {
+	t.Setenv("CORE_WORKSPACE", t.TempDir())
+	t.Setenv("FORGE_TOKEN", "")
+	t.Setenv("FORGE_URL", "")
+
+	c := core.New(core.WithService(Register))
+
+	// Register stores agents.concurrency into Core Config — verify it is present
+	concurrency := core.ConfigGet[map[string]ConcurrencyLimit](c.Config(), "agents.concurrency")
+	assert.NotNil(t, concurrency, "Register must store agents.concurrency in Core Config")
+}
+
+// --- OnStartup ---
+
+func TestOnStartup_Good_CreatesPokeCh(t *testing.T) {
+	t.Setenv("CORE_WORKSPACE", t.TempDir())
+	t.Setenv("CORE_AGENT_DISPATCH", "")
+
+	c := core.New(core.WithOption("name", "test"))
+	s := NewPrep()
+	s.SetCore(c)
+
+	assert.Nil(t, s.pokeCh, "pokeCh should be nil before OnStartup")
+
+	err := s.OnStartup(context.Background())
+	require.NoError(t, err)
+
+	assert.NotNil(t, s.pokeCh, "OnStartup must initialise pokeCh via StartRunner")
+}
+
+func TestOnStartup_Good_FrozenByDefault(t *testing.T) {
+	t.Setenv("CORE_WORKSPACE", t.TempDir())
+	t.Setenv("CORE_AGENT_DISPATCH", "")
+
+	c := core.New(core.WithOption("name", "test"))
+	s := NewPrep()
+	s.SetCore(c)
+
+	require.NoError(t, s.OnStartup(context.Background()))
+	assert.True(t, s.frozen, "queue must be frozen after OnStartup without CORE_AGENT_DISPATCH=1")
+}
+
+func TestOnStartup_Good_NoError(t *testing.T) {
+	t.Setenv("CORE_WORKSPACE", t.TempDir())
+	t.Setenv("CORE_AGENT_DISPATCH", "")
+
+	c := core.New(core.WithOption("name", "test"))
+	s := NewPrep()
+	s.SetCore(c)
+
+	err := s.OnStartup(context.Background())
+	assert.NoError(t, err)
+}
+
+// --- OnShutdown ---
+
+func TestOnShutdown_Good_FreezesQueue(t *testing.T) {
+	t.Setenv("CORE_WORKSPACE", t.TempDir())
+
+	s := &PrepSubsystem{frozen: false}
+	err := s.OnShutdown(context.Background())
+	require.NoError(t, err)
+	assert.True(t, s.frozen, "OnShutdown must set frozen=true")
+}
+
+func TestOnShutdown_Good_AlreadyFrozen(t *testing.T) {
+	// Calling OnShutdown twice must be idempotent
+	s := &PrepSubsystem{frozen: true}
+	err := s.OnShutdown(context.Background())
+	require.NoError(t, err)
+	assert.True(t, s.frozen)
+}
+
+func TestOnShutdown_Good_NoError(t *testing.T) {
+	s := &PrepSubsystem{}
+	assert.NoError(t, s.OnShutdown(context.Background()))
+}
+
+func TestOnShutdown_Ugly_NilCore(t *testing.T) {
+	// OnShutdown must not panic even if s.core is nil
+	s := &PrepSubsystem{core: nil, frozen: false}
+	assert.NotPanics(t, func() {
+		_ = s.OnShutdown(context.Background())
+	})
+	assert.True(t, s.frozen)
+}
diff --git a/pkg/agentic/status_logic_test.go b/pkg/agentic/status_logic_test.go
new file mode 100644
index 0000000..a934941
--- /dev/null
+++ b/pkg/agentic/status_logic_test.go
@@ -0,0 +1,176 @@
+// SPDX-License-Identifier: EUPL-1.2
+
+package agentic
+
+import (
+	"encoding/json"
+	"path/filepath"
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+// --- ReadStatus ---
+
+func TestReadStatus_Good_AllFields(t *testing.T) {
+	dir := t.TempDir()
+	now := time.Now().Truncate(time.Second)
+
+	original := WorkspaceStatus{
+		Status:    "running",
+		Agent:     "claude:opus",
+		Repo:      "go-io",
+		Org:       "core",
+		Task:      "add observability",
+		Branch:    "agent/add-observability",
+		Issue:     7,
+		PID:       42100,
+		StartedAt: now,
+		UpdatedAt: now,
+		Question:  "",
+		Runs:      2,
+		PRURL:     "",
+	}
+	data, err := json.MarshalIndent(original, "", "  ")
+	require.NoError(t, err)
+	require.True(t, fs.Write(filepath.Join(dir, "status.json"), string(data)).OK)
+
+	st, err := ReadStatus(dir)
+	require.NoError(t, err)
+
+	assert.Equal(t, original.Status, st.Status)
+	assert.Equal(t, original.Agent, st.Agent)
+	assert.Equal(t, original.Repo, st.Repo)
+	assert.Equal(t, original.Org, st.Org)
+	assert.Equal(t, original.Task, st.Task)
+	assert.Equal(t, original.Branch, st.Branch)
+	assert.Equal(t, original.Issue, st.Issue)
+	assert.Equal(t, original.PID, st.PID)
+	assert.Equal(t, original.Runs, st.Runs)
+}
+
+func TestReadStatus_Bad_MissingFile(t *testing.T) {
+	dir := t.TempDir()
+	_, err := ReadStatus(dir)
+	assert.Error(t, err, "missing status.json must return an error")
+}
+
+func TestReadStatus_Bad_CorruptJSON(t *testing.T) {
+	dir := t.TempDir()
+	require.True(t, fs.Write(filepath.Join(dir, "status.json"), `{"status": "running", broken`).OK)
+
+	_, err := ReadStatus(dir)
+	assert.Error(t, err, "corrupt JSON must return an error")
+}
+
+func TestReadStatus_Bad_NullJSON(t *testing.T) {
+	dir := t.TempDir()
+	require.True(t, fs.Write(filepath.Join(dir, "status.json"), "null").OK)
+
+	// null is valid JSON — ReadStatus returns a zero-value struct, not an error
+	st, err := ReadStatus(dir)
+	require.NoError(t, err)
+	assert.Equal(t, "", st.Status)
+}
+
+// --- writeStatus ---
+
+func TestWriteStatus_Good_WritesAndReadsBack(t *testing.T) {
+	dir := t.TempDir()
+	st := &WorkspaceStatus{
+		Status: "queued",
+		Agent:  "gemini:pro",
+		Repo:   "go-log",
+		Task:   "improve logging",
+		Runs:   0,
+	}
+
+	err := writeStatus(dir, st)
+	require.NoError(t, err)
+
+	read, err := ReadStatus(dir)
+	require.NoError(t, err)
+	assert.Equal(t, "queued", read.Status)
+	assert.Equal(t, "gemini:pro", read.Agent)
+	assert.Equal(t, "go-log", read.Repo)
+	assert.Equal(t, "improve logging", read.Task)
+}
+
+func TestWriteStatus_Good_SetsUpdatedAt(t *testing.T) {
+	dir := t.TempDir()
+	before := time.Now().Add(-time.Millisecond)
+
+	st := &WorkspaceStatus{Status: "failed", Agent: "codex"}
+	err := writeStatus(dir, st)
+	require.NoError(t, err)
+
+	assert.True(t, st.UpdatedAt.After(before), "writeStatus must set UpdatedAt to a recent time")
+}
+
+func TestWriteStatus_Good_Overwrites(t *testing.T) {
+	dir := t.TempDir()
+
+	require.NoError(t, writeStatus(dir, &WorkspaceStatus{Status: "running", Agent: "gemini"}))
+	require.NoError(t, writeStatus(dir, &WorkspaceStatus{Status: "completed", Agent: "gemini"}))
+
+	st, err := ReadStatus(dir)
+	require.NoError(t, err)
+	assert.Equal(t, "completed", st.Status)
+}
+
+// --- WorkspaceStatus JSON round-trip ---
+
+func TestWorkspaceStatus_Good_JSONRoundTrip(t *testing.T) {
+	now := time.Now().Truncate(time.Second)
+	original := WorkspaceStatus{
+		Status:    "blocked",
+		Agent:     "codex:gpt-5.4",
+		Repo:      "agent",
+		Org:       "core",
+		Task:      "write more tests",
+		Branch:    "agent/write-more-tests",
+		Issue:     15,
+		PID:       99001,
+		StartedAt: now,
+		UpdatedAt: now,
+		Question:  "Which pattern should I use?",
+		Runs:      3,
+		PRURL:     "https://forge.lthn.ai/core/agent/pulls/10",
+	}
+
+	data, err := json.Marshal(original)
+	require.NoError(t, err)
+
+	var decoded WorkspaceStatus
+	require.NoError(t, json.Unmarshal(data, &decoded))
+
+	assert.Equal(t, original.Status, decoded.Status)
+	assert.Equal(t, original.Agent, decoded.Agent)
+	assert.Equal(t, original.Repo, decoded.Repo)
+	assert.Equal(t, original.Org, decoded.Org)
+	assert.Equal(t, original.Task, decoded.Task)
+	assert.Equal(t, original.Branch, decoded.Branch)
+	assert.Equal(t, original.Issue, decoded.Issue)
+	assert.Equal(t, original.PID, decoded.PID)
+	assert.Equal(t, original.Question, decoded.Question)
+	assert.Equal(t, original.Runs, decoded.Runs)
+	assert.Equal(t, original.PRURL, decoded.PRURL)
+}
+
+func TestWorkspaceStatus_Good_OmitemptyFields(t *testing.T) {
+	st := WorkspaceStatus{Status: "queued", Agent: "claude"}
+
+	data, err := json.Marshal(st)
+	require.NoError(t, err)
+
+	// Optional fields with omitempty must be absent when zero
+	jsonStr := string(data)
+	assert.NotContains(t, jsonStr, `"org"`)
+	assert.NotContains(t, jsonStr, `"branch"`)
+	assert.NotContains(t, jsonStr, `"question"`)
+	assert.NotContains(t, jsonStr, `"pr_url"`)
+	assert.NotContains(t, jsonStr, `"pid"`)
+	assert.NotContains(t, jsonStr, `"issue"`)
+}