feat(coder-labs/modules/codex): add support for agentapi state_persistence (#785)

## Description

- add support for agentapi state_persistence

## Type of Change

- [ ] New module
- [ ] New template
- [ ] Bug fix
- [x] Feature/enhancement
- [x] Documentation
- [ ] Other

## Module Information

<!-- Delete this section if not applicable -->

**Path:** `registry/coder-labs/modules/codex`  
**New version:** `v4.2.0`  
**Breaking change:** [ ] Yes [x] No

## Testing & Validation

- [x] Tests pass (`bun test`)
- [x] Code formatted (`bun fmt`)
- [x] Changes tested locally

## Related Issues

Closes: #783

registry/coder-labs/modules/codex/README.md

@@ -13,7 +13,7 @@ Run Codex CLI in your workspace to access OpenAI's models through the Codex inte
 ```tf
 module "codex" {
   source         = "registry.coder.com/coder-labs/codex/coder"
-  version        = "4.1.2"
+  version        = "4.2.0"
   agent_id       = coder_agent.example.id
   openai_api_key = var.openai_api_key
   workdir        = "/home/coder/project"
@@ -32,7 +32,7 @@ module "codex" {
 module "codex" {
   count          = data.coder_workspace.me.start_count
   source         = "registry.coder.com/coder-labs/codex/coder"
-  version        = "4.1.2"
+  version        = "4.2.0"
   agent_id       = coder_agent.example.id
   openai_api_key = "..."
   workdir        = "/home/coder/project"
@@ -51,7 +51,7 @@ For tasks integration with AI Bridge, add `enable_aibridge = true` to the [Usage
 ```tf
 module "codex" {
   source          = "registry.coder.com/coder-labs/codex/coder"
-  version         = "4.1.2"
+  version         = "4.2.0"
   agent_id        = coder_agent.example.id
   workdir         = "/home/coder/project"
   enable_aibridge = true
@@ -63,6 +63,8 @@ When `enable_aibridge = true`, the module:
 - Configures Codex to use the AI Bridge profile with `base_url` pointing to `${data.coder_workspace.me.access_url}/api/v2/aibridge/openai/v1` and `env_key` pointing to the workspace owner's session token
 
 ```toml
+profile = "aibridge" # sets the default profile to aibridge
+
 [model_providers.aibridge]
 name = "AI Bridge"
 base_url = "https://example.coder.com/api/v2/aibridge/openai/v1"
@@ -75,8 +77,6 @@ model = "<model>" # as configured in the module input
 model_reasoning_effort = "<model_reasoning_effort>" # as configured in the module input
 ```
 
-Codex then runs with `--profile aibridge`
-
 This allows Codex to route API requests through Coder's AI Bridge instead of directly to OpenAI's API.
 Template build will fail if `openai_api_key` is provided alongside `enable_aibridge = true`.
 
@@ -94,7 +94,7 @@ data "coder_task" "me" {}
 
 module "codex" {
   source         = "registry.coder.com/coder-labs/codex/coder"
-  version        = "4.1.2"
+  version        = "4.2.0"
   agent_id       = coder_agent.example.id
   openai_api_key = "..."
   ai_prompt      = data.coder_task.me.prompt
@@ -112,7 +112,7 @@ This example shows additional configuration options for custom models, MCP serve
 ```tf
 module "codex" {
   source         = "registry.coder.com/coder-labs/codex/coder"
-  version        = "4.1.2"
+  version        = "4.2.0"
   agent_id       = coder_agent.example.id
   openai_api_key = "..."
   workdir        = "/home/coder/project"
@@ -148,6 +148,19 @@ module "codex" {
 - **Configuration**: Sets `OPENAI_API_KEY` environment variable and passes `--model` flag to Codex CLI (if variables provided)
 - **Session Continuity**: When `continue = true` (default), the module automatically tracks task sessions in `~/.codex-module/.codex-task-session`. On workspace restart, it resumes the existing session with full conversation history. Set `continue = false` to always start fresh sessions.
 
+## State Persistence
+
+AgentAPI can save and restore its conversation state to disk across workspace restarts. This complements `continue` (which resumes the Codex CLI session) by also preserving the AgentAPI-level context. Enabled by default, requires agentapi >= v0.12.0 (older versions skip it with a warning).
+
+To disable:
+
+```tf
+module "codex" {
+  # ... other config
+  enable_state_persistence = false
+}
+```
+
 ## Configuration
 
 ### Default Configuration

registry/coder-labs/modules/codex/main.tf

@@ -131,7 +131,7 @@ variable "install_agentapi" {
 variable "agentapi_version" {
   type        = string
   description = "The version of AgentAPI to install."
-  default     = "v0.11.8"
+  default     = "v0.12.1"
 }
 
 variable "codex_model" {
@@ -164,6 +164,12 @@ variable "continue" {
   default     = true
 }
 
+variable "enable_state_persistence" {
+  type        = bool
+  description = "Enable AgentAPI conversation state persistence across restarts."
+  default     = true
+}
+
 variable "codex_system_prompt" {
   type        = string
   description = "System instructions written to AGENTS.md in the ~/.codex directory"
@@ -206,7 +212,7 @@ locals {
 
 module "agentapi" {
   source  = "registry.coder.com/coder/agentapi/coder"
-  version = "2.0.0"
+  version = "2.2.0"
 
   agent_id                 = var.agent_id
   folder                   = local.workdir
@@ -222,6 +228,7 @@ module "agentapi" {
   install_agentapi         = var.install_agentapi
   agentapi_subdomain       = var.subdomain
   agentapi_version         = var.agentapi_version
+  enable_state_persistence = var.enable_state_persistence
   pre_install_script       = var.pre_install_script
   post_install_script      = var.post_install_script
   start_script             = <<-EOT

registry/coder-labs/modules/codex/main.tftest.hcl

@@ -0,0 +1,187 @@
+run "test_codex_basic" {
+  command = plan
+
+  variables {
+    agent_id       = "test-agent"
+    workdir        = "/home/coder"
+    openai_api_key = "test-key"
+  }
+
+  assert {
+    condition     = var.agent_id == "test-agent"
+    error_message = "Agent ID should be set correctly"
+  }
+
+  assert {
+    condition     = var.workdir == "/home/coder"
+    error_message = "Workdir should be set correctly"
+  }
+
+  assert {
+    condition     = var.install_codex == true
+    error_message = "install_codex should default to true"
+  }
+
+  assert {
+    condition     = var.install_agentapi == true
+    error_message = "install_agentapi should default to true"
+  }
+
+  assert {
+    condition     = var.report_tasks == true
+    error_message = "report_tasks should default to true"
+  }
+
+  assert {
+    condition     = var.continue == true
+    error_message = "continue should default to true"
+  }
+}
+
+run "test_enable_state_persistence_default" {
+  command = plan
+
+  variables {
+    agent_id       = "test-agent"
+    workdir        = "/home/coder"
+    openai_api_key = "test-key"
+  }
+
+  assert {
+    condition     = var.enable_state_persistence == true
+    error_message = "enable_state_persistence should default to true"
+  }
+}
+
+run "test_disable_state_persistence" {
+  command = plan
+
+  variables {
+    agent_id                 = "test-agent"
+    workdir                  = "/home/coder"
+    openai_api_key           = "test-key"
+    enable_state_persistence = false
+  }
+
+  assert {
+    condition     = var.enable_state_persistence == false
+    error_message = "enable_state_persistence should be false when explicitly disabled"
+  }
+}
+
+run "test_codex_with_aibridge" {
+  command = plan
+
+  variables {
+    agent_id        = "test-agent"
+    workdir         = "/home/coder"
+    enable_aibridge = true
+  }
+
+  assert {
+    condition     = var.enable_aibridge == true
+    error_message = "enable_aibridge should be set to true"
+  }
+}
+
+run "test_aibridge_disabled_with_api_key" {
+  command = plan
+
+  variables {
+    agent_id        = "test-agent"
+    workdir         = "/home/coder"
+    openai_api_key  = "test-key"
+    enable_aibridge = false
+  }
+
+  assert {
+    condition     = var.enable_aibridge == false
+    error_message = "enable_aibridge should be false"
+  }
+
+  assert {
+    condition     = coder_env.openai_api_key.value == "test-key"
+    error_message = "OpenAI API key should be set correctly"
+  }
+}
+
+run "test_custom_options" {
+  command = plan
+
+  variables {
+    agent_id             = "test-agent"
+    workdir              = "/home/coder/project"
+    openai_api_key       = "test-key"
+    order                = 5
+    group                = "ai-tools"
+    icon                 = "/icon/custom.svg"
+    web_app_display_name = "Custom Codex"
+    cli_app              = true
+    cli_app_display_name = "Codex Terminal"
+    subdomain            = true
+    report_tasks         = false
+    continue             = false
+    codex_model          = "gpt-4o"
+    codex_version        = "0.1.0"
+    agentapi_version     = "v0.12.0"
+  }
+
+  assert {
+    condition     = var.order == 5
+    error_message = "Order should be set to 5"
+  }
+
+  assert {
+    condition     = var.group == "ai-tools"
+    error_message = "Group should be set to 'ai-tools'"
+  }
+
+  assert {
+    condition     = var.icon == "/icon/custom.svg"
+    error_message = "Icon should be set to custom icon"
+  }
+
+  assert {
+    condition     = var.cli_app == true
+    error_message = "cli_app should be enabled"
+  }
+
+  assert {
+    condition     = var.subdomain == true
+    error_message = "subdomain should be enabled"
+  }
+
+  assert {
+    condition     = var.report_tasks == false
+    error_message = "report_tasks should be disabled"
+  }
+
+  assert {
+    condition     = var.continue == false
+    error_message = "continue should be disabled"
+  }
+
+  assert {
+    condition     = var.codex_model == "gpt-4o"
+    error_message = "codex_model should be set to 'gpt-4o'"
+  }
+}
+
+run "test_no_api_key_no_aibridge" {
+  command = plan
+
+  variables {
+    agent_id = "test-agent"
+    workdir  = "/home/coder"
+  }
+
+  assert {
+    condition     = var.openai_api_key == ""
+    error_message = "openai_api_key should be empty when not provided"
+  }
+
+  assert {
+    condition     = var.enable_aibridge == false
+    error_message = "enable_aibridge should default to false"
+  }
+}