feat(codex): ship native basecamp plugin

.codex-plugin/plugin.json

@@ -0,0 +1,34 @@
+{
+  "name": "basecamp",
+  "version": "0.7.2",
+  "description": "Use Basecamp from Codex to find work, create todos, and keep projects up to date.",
+  "author": {
+    "name": "37signals",
+    "email": "support@37signals.com",
+    "url": "https://37signals.com"
+  },
+  "homepage": "https://basecamp.com/cli",
+  "repository": "https://github.com/basecamp/basecamp-cli",
+  "license": "MIT",
+  "skills": "./skills/",
+  "interface": {
+    "displayName": "Basecamp",
+    "shortDescription": "Work with Basecamp from Codex.",
+    "longDescription": "Find assignments, create and update Basecamp work, and diagnose the integration. Requires the Basecamp CLI (basecamp) installed and on your PATH.",
+    "developerName": "37signals",
+    "category": "Productivity",
+    "capabilities": [
+      "Interactive",
+      "Read",
+      "Write"
+    ],
+    "websiteURL": "https://basecamp.com/cli",
+    "defaultPrompt": [
+      "Show my assigned Basecamp work and highlight anything overdue.",
+      "Create a Basecamp todo from this task and assign it to me.",
+      "Summarize recent activity in the current Basecamp project."
+    ],
+    "composerIcon": "./assets/bc5-snowglobe.png",
+    "logo": "./assets/bc5-snowglobe.png"
+  }
+}

.goreleaser.yaml

@@ -6,7 +6,7 @@ project_name: basecamp
 before:
   hooks:
     - sh -c 'mkdir -p completions && go run ./cmd/basecamp completion bash > completions/basecamp.bash && go run ./cmd/basecamp completion zsh > completions/_basecamp && go run ./cmd/basecamp completion fish > completions/basecamp.fish'
-    - sh -c '{{ if .Prerelease }}echo "Skipping Claude plugin version stamp for prerelease {{ .Version }}"{{ else }}scripts/stamp-plugin-version.sh {{ .Version }}{{ end }}'
+    - sh -c '{{ if .Prerelease }}echo "Skipping plugin version stamps for prerelease {{ .Version }}"{{ else }}scripts/stamp-plugin-version.sh {{ .Version }} && scripts/stamp-codex-plugin-version.sh {{ .Version }}{{ end }}'
 
 builds:
   - id: basecamp

.surface

@@ -845,6 +845,7 @@ CMD basecamp search metadata
 CMD basecamp search types
 CMD basecamp setup
 CMD basecamp setup claude
+CMD basecamp setup codex
 CMD basecamp show
 CMD basecamp skill
 CMD basecamp skill install
@@ -11394,6 +11395,27 @@ FLAG basecamp setup claude --stats type=bool
 FLAG basecamp setup claude --styled type=bool
 FLAG basecamp setup claude --todolist type=string
 FLAG basecamp setup claude --verbose type=count
+FLAG basecamp setup codex --account type=string
+FLAG basecamp setup codex --agent type=bool
+FLAG basecamp setup codex --cache-dir type=string
+FLAG basecamp setup codex --count type=bool
+FLAG basecamp setup codex --help type=bool
+FLAG basecamp setup codex --hints type=bool
+FLAG basecamp setup codex --ids-only type=bool
+FLAG basecamp setup codex --in type=string
+FLAG basecamp setup codex --jq type=string
+FLAG basecamp setup codex --json type=bool
+FLAG basecamp setup codex --markdown type=bool
+FLAG basecamp setup codex --md type=bool
+FLAG basecamp setup codex --no-hints type=bool
+FLAG basecamp setup codex --no-stats type=bool
+FLAG basecamp setup codex --profile type=string
+FLAG basecamp setup codex --project type=string
+FLAG basecamp setup codex --quiet type=bool
+FLAG basecamp setup codex --stats type=bool
+FLAG basecamp setup codex --styled type=bool
+FLAG basecamp setup codex --todolist type=string
+FLAG basecamp setup codex --verbose type=count
 FLAG basecamp show --account type=string
 FLAG basecamp show --agent type=bool
 FLAG basecamp show --all-comments type=bool
@@ -16394,6 +16416,7 @@ SUB basecamp search metadata
 SUB basecamp search types
 SUB basecamp setup
 SUB basecamp setup claude
+SUB basecamp setup codex
 SUB basecamp show
 SUB basecamp skill
 SUB basecamp skill install

AGENTS.md

@@ -35,7 +35,8 @@ basecamp-cli/
 │   └── version/      # Version info
 ├── e2e/              # BATS integration tests
 ├── skills/           # Agent skills
-└── .claude-plugin/   # Claude Code integration
+├── .claude-plugin/   # Claude Code integration
+└── .codex-plugin/    # Codex plugin manifest
 ```
 
 ## Basecamp API Reference

Makefile

@@ -401,6 +401,7 @@ check-surface-compat: build
 .PHONY: check-skill-drift
 check-skill-drift:
 	@scripts/check-skill-drift.sh
+	@scripts/check-skill-drift.sh skills/basecamp-doctor/SKILL.md
 
 # Verify group commands show help bare (no RunE on parents with subcommands)
 .PHONY: check-bare-groups

README.md

@@ -5,7 +5,7 @@
 - Works standalone or with any AI agent (Claude, Codex, Copilot, Gemini)
 - JSON output with breadcrumbs for easy navigation
 - OAuth authentication with automatic token refresh
-- Includes agent skill and Claude plugin
+- Includes agent skills plus native Claude Code and Codex plugins
 
 ## Quick Start
 
@@ -148,7 +148,21 @@ Both `BASECAMP_OAUTH_CLIENT_ID` and `BASECAMP_OAUTH_CLIENT_SECRET` must be set t
 
 `basecamp` works with any AI agent that can run shell commands.
 
-**Claude Code:** `basecamp setup claude` — installs the plugin with skills, hooks, and agent workflow support.
+Both plugins require the `basecamp` CLI installed and on your PATH.
+
+**Claude Code:** `basecamp setup claude` — installs the plugin with skills and agent workflow support.
+
+**Codex:** `basecamp setup codex` — registers the 37signals marketplace and installs the native plugin with Basecamp skills and diagnostics. Start a new Codex thread afterward to load the skills.
+
+Manual Codex installation uses the same marketplace:
+
+```bash
+codex plugin marketplace add basecamp/claude-plugins
+codex plugin add basecamp@37signals
+```
+
+To pick up a newer plugin version later, refresh the marketplace with
+`codex plugin marketplace upgrade 37signals` (or re-run `basecamp setup codex`).
 
 **Other agents:** Point your agent at [`skills/basecamp/SKILL.md`](skills/basecamp/SKILL.md) for Basecamp workflow coverage.
 
@@ -180,6 +194,7 @@ See [install.md](install.md) for step-by-step setup instructions.
 ```bash
 basecamp doctor              # Check CLI health and diagnose issues
 basecamp doctor --verbose    # Verbose output with details
+basecamp doctor --json       # Structured checks, including Claude and Codex
 ```
 
 ## Development

RELEASING.md

@@ -23,7 +23,7 @@ make release VERSION=0.2.0 DRY_RUN=1
 1. Validates semver format, main branch, clean tree, synced with remote
 2. Checks for `replace` directives in go.mod
 3. Runs `make release-check` (quality checks, vuln scan, replace-check, race-test, surface compat)
-4. Updates stable release metadata (`nix/package.nix` and `.claude-plugin/plugin.json`) for stable versions
+4. Updates stable release metadata (`nix/package.nix`, `.claude-plugin/plugin.json`, and `.codex-plugin/plugin.json`) for stable versions
 5. Creates annotated tag `v$VERSION` and pushes to origin
 6. GitHub Actions [release workflow](.github/workflows/release.yml) runs:
    - Security scan + full test suite + CLI surface compatibility check
@@ -58,6 +58,7 @@ manager channels and agent distribution metadata on the latest stable version.
 | AUR | Updates the `basecamp-cli` package when `AUR_KEY` is configured. | The stable AUR package remains active. |
 | Nix flake | Updates `nix/package.nix` and verifies the flake. | Nix metadata remains on the latest stable version. |
 | Claude plugin metadata | Updates `.claude-plugin/plugin.json`. | Plugin metadata remains on the latest stable version. |
+| Codex plugin metadata | Updates `.codex-plugin/plugin.json`. | Plugin metadata remains on the latest stable version. |
 | Skills distribution | Syncs skills to the distribution repo. | Uses the skill embedded in the prerelease binary. |
 
 The prerelease binary embeds the matching `skills/basecamp/SKILL.md`. Testers can

install.md

@@ -112,13 +112,38 @@ EXECUTE NOW: Start with Step 1. Mark TODO items complete as you go. Stop when `b
 
 **Do not execute this section unless explicitly requested.** The core installation is complete when DONE WHEN passes.
 
+Both agent plugins require the `basecamp` CLI installed above — the plugin invokes it for every Basecamp operation.
+
 ### Claude Code
 
 ```bash
 basecamp setup claude
 ```
 
-This registers the marketplace and installs the plugin with skills, hooks, and agent workflow support.
+This registers the marketplace and installs the plugin with skills and agent workflow support.
+
+### Codex
+
+```bash
+basecamp setup codex
+```
+
+This installs the shared Basecamp skill, registers the 37signals Codex marketplace, and installs the native plugin. Start a new Codex thread after setup to load the skills.
+
+For a manual install:
+
+```bash
+codex plugin marketplace add basecamp/claude-plugins
+codex plugin add basecamp@37signals
+```
+
+To pick up a newer plugin version later, refresh with `codex plugin marketplace upgrade 37signals` (or re-run `basecamp setup codex`).
+
+Verify either agent integration with structured diagnostics:
+
+```bash
+basecamp doctor --json
+```
 
 ### Other Agents
 

internal/commands/doctor.go

@@ -206,28 +206,20 @@ func runDoctorChecks(ctx context.Context, app *appctx.App, verbose bool) []Check
 		checks = append(checks, checkSkillVersion())
 	}
 	for _, agent := range harness.DetectedAgents() {
-		if agent.Checks != nil {
-			for _, c := range agent.Checks() {
-				checks = append(checks, Check{
-					Name:    c.Name,
-					Status:  c.Status,
-					Message: c.Message,
-					Hint:    c.Hint,
-				})
-			}
+		var agentChecks []*harness.StatusCheck
+		if agent.Diagnostics != nil {
+			agentChecks = agent.Diagnostics(ctx)
+		} else if agent.Checks != nil {
+			agentChecks = agent.Checks()
+		}
+		for _, c := range agentChecks {
+			checks = append(checks, Check{
+				Name:    c.Name,
+				Status:  c.Status,
+				Message: c.Message,
+				Hint:    c.Hint,
+			})
 		}
-	}
-
-	// 13. Claude plugin version (doctor-only, not part of generic agent checks
-	//     which gate setup wizard behavior)
-	if harness.DetectClaude() {
-		pvc := harness.CheckClaudePluginVersion()
-		checks = append(checks, Check{
-			Name:    pvc.Name,
-			Status:  pvc.Status,
-			Message: pvc.Message,
-			Hint:    pvc.Hint,
-		})
 	}
 
 	return checks
@@ -985,6 +977,12 @@ func buildDoctorBreadcrumbs(checks []Check) []output.Breadcrumb {
 				Cmd:         "basecamp skill install",
 				Description: "Update installed skill",
 			})
+		case "Codex Plugin", "Codex Plugin Version":
+			breadcrumbs = append(breadcrumbs, output.Breadcrumb{
+				Action:      "setup_codex",
+				Cmd:         "basecamp setup codex",
+				Description: "Install or update the Codex plugin",
+			})
 		}
 	}
 

internal/commands/doctor_test.go

@@ -5,6 +5,7 @@ import (
 	"context"
 	"os"
 	"path/filepath"
+	"strings"
 	"testing"
 
 	"github.com/spf13/cobra"
@@ -662,6 +663,51 @@ func TestBuildDoctorBreadcrumbs_SkillVersionWarn(t *testing.T) {
 	assert.Equal(t, "basecamp skill install", breadcrumbs[0].Cmd)
 }
 
+func TestCheckCodexIntegrationIncludesVersion(t *testing.T) {
+	logPath := installCodexStub(t, codexStubOptions{pluginAlreadyInstalled: true})
+	app, _ := setupDoctorTestApp(t, "")
+
+	checks := runDoctorChecks(context.Background(), app, false)
+	var names []string
+	for _, check := range checks {
+		if check.Name == "Codex Plugin" || check.Name == "Codex Plugin Version" {
+			names = append(names, check.Name)
+		}
+	}
+	require.Equal(t, []string{"Codex Plugin", "Codex Plugin Version"}, names)
+	assert.Equal(t, 1, strings.Count(readCodexSetupCalls(t, logPath), "plugin list --available --json"))
+}
+
+func TestCheckCodexIntegrationWarnsOnVersionMismatch(t *testing.T) {
+	installCodexStub(t, codexStubOptions{pluginAlreadyInstalled: true})
+	app, _ := setupDoctorTestApp(t, "")
+	original := version.Version
+	version.Version = "0.8.0"
+	t.Cleanup(func() { version.Version = original })
+
+	checks := runDoctorChecks(context.Background(), app, false)
+	for _, check := range checks {
+		if check.Name == "Codex Plugin Version" {
+			assert.Equal(t, "warn", check.Status)
+			assert.Contains(t, check.Hint, "basecamp setup codex")
+			return
+		}
+	}
+	t.Fatal("Codex Plugin Version check not found")
+}
+
+func TestBuildDoctorBreadcrumbs_Codex(t *testing.T) {
+	checks := []Check{
+		{Name: "Codex Plugin", Status: "fail"},
+		{Name: "Codex Plugin Version", Status: "warn"},
+	}
+
+	breadcrumbs := buildDoctorBreadcrumbs(checks)
+
+	require.Len(t, breadcrumbs, 1)
+	assert.Equal(t, "basecamp setup codex", breadcrumbs[0].Cmd)
+}
+
 func TestCheckLegacyInstall_SkipsKeyringWhenNoKeyring(t *testing.T) {
 	t.Setenv("BASECAMP_NO_KEYRING", "1")
 	t.Setenv("XDG_CACHE_HOME", t.TempDir())