fix: resolve issues with claude-code session resumption (#496)

## Description

Fixes session resumption logic by having the continue flag decide
whether to continue a workspace based on session history

## Type of Change

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

## Module Information

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

**Path:** `registry/coder/modules/claude-code`  
**New version:** `v3.2.2`  
**Breaking change:** [ ] Yes [X] No

## Testing & Validation

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

## Related Issues

<!-- Link related issues or write "None" if not applicable -->

---------

Co-authored-by: Copilot <[email protected]>

Author: DevelopmentCats

registry/coder/modules/claude-code/README.md

@@ -13,7 +13,7 @@ Run the [Claude Code](https://docs.anthropic.com/en/docs/agents-and-tools/claude
 ```tf
 module "claude-code" {
   source         = "registry.coder.com/coder/claude-code/coder"
-  version        = "3.2.1"
+  version        = "3.2.2"
   agent_id       = coder_agent.example.id
   workdir        = "/home/coder/project"
   claude_api_key = "xxxx-xxxxx-xxxx"
@@ -32,6 +32,10 @@ module "claude-code" {
   - You can get the API key from the [Anthropic Console](https://console.anthropic.com/dashboard).
   - You can get the Session Token using the `claude setup-token` command. This is a long-lived authentication token (requires Claude subscription)
 
+### Session Resumption Behavior
+
+By default, Claude Code automatically resumes existing conversations when your workspace restarts. Sessions are tracked per workspace directory, so conversations continue where you left off. If no session exists (first start), your `ai_prompt` will run normally. To disable this behavior and always start fresh, set `continue = false`
+
 ## Examples
 
 ### Usage with Agent Boundaries
@@ -66,7 +70,7 @@ data "coder_parameter" "ai_prompt" {
 
 module "claude-code" {
   source   = "registry.coder.com/coder/claude-code/coder"
-  version  = "3.2.1"
+  version  = "3.2.2"
   agent_id = coder_agent.example.id
   workdir  = "/home/coder/project"
 
@@ -102,7 +106,7 @@ Run and configure Claude Code as a standalone CLI in your workspace.
 ```tf
 module "claude-code" {
   source              = "registry.coder.com/coder/claude-code/coder"
-  version             = "3.2.1"
+  version             = "3.2.2"
   agent_id            = coder_agent.example.id
   workdir             = "/home/coder"
   install_claude_code = true
@@ -125,7 +129,7 @@ variable "claude_code_oauth_token" {
 
 module "claude-code" {
   source                  = "registry.coder.com/coder/claude-code/coder"
-  version                 = "3.2.1"
+  version                 = "3.2.2"
   agent_id                = coder_agent.example.id
   workdir                 = "/home/coder/project"
   claude_code_oauth_token = var.claude_code_oauth_token
@@ -198,7 +202,7 @@ resource "coder_env" "bedrock_api_key" {
 
 module "claude-code" {
   source   = "registry.coder.com/coder/claude-code/coder"
-  version  = "3.2.1"
+  version  = "3.2.2"
   agent_id = coder_agent.example.id
   workdir  = "/home/coder/project"
   model    = "global.anthropic.claude-sonnet-4-5-20250929-v1:0"
@@ -255,7 +259,7 @@ resource "coder_env" "google_application_credentials" {
 
 module "claude-code" {
   source   = "registry.coder.com/coder/claude-code/coder"
-  version  = "3.2.1"
+  version  = "3.2.2"
   agent_id = coder_agent.example.id
   workdir  = "/home/coder/project"
   model    = "claude-sonnet-4@20250514"

registry/coder/modules/claude-code/main.test.ts

@@ -167,7 +167,7 @@ describe("claude-code", async () => {
     const { id } = await setup({
       moduleVariables: {
         permission_mode: mode,
-        task_prompt: "test prompt",
+        ai_prompt: "test prompt",
       },
     });
     await execModuleScript(id);
@@ -185,7 +185,7 @@ describe("claude-code", async () => {
     const { id } = await setup({
       moduleVariables: {
         model: model,
-        task_prompt: "test prompt",
+        ai_prompt: "test prompt",
       },
     });
     await execModuleScript(id);
@@ -198,21 +198,34 @@ describe("claude-code", async () => {
     expect(startLog.stdout).toContain(`--model ${model}`);
   });
 
-  test("claude-continue-previous-conversation", async () => {
+  test("claude-continue-resume-existing-session", async () => {
     const { id } = await setup({
       moduleVariables: {
         continue: "true",
-        task_prompt: "test prompt",
+        ai_prompt: "test prompt",
       },
     });
+
+    // Create a mock session file with the predefined task session ID
+    const taskSessionId = "cd32e253-ca16-4fd3-9825-d837e74ae3c2";
+    const sessionDir = `/home/coder/.claude/projects/-home-coder-project`;
+    await execContainer(id, ["mkdir", "-p", sessionDir]);
+    await execContainer(id, [
+      "bash",
+      "-c",
+      `touch ${sessionDir}/session-${taskSessionId}.jsonl`,
+    ]);
+
     await execModuleScript(id);
 
     const startLog = await execContainer(id, [
       "bash",
       "-c",
       "cat /home/coder/.claude-module/agentapi-start.log",
     ]);
-    expect(startLog.stdout).toContain("--continue");
+    expect(startLog.stdout).toContain("--resume");
+    expect(startLog.stdout).toContain(taskSessionId);
+    expect(startLog.stdout).toContain("Resuming existing task session");
   });
 
   test("pre-post-install-scripts", async () => {

registry/coder/modules/claude-code/main.tf

@@ -134,8 +134,8 @@ variable "resume_session_id" {
 
 variable "continue" {
   type        = bool
-  description = "Load the most recent conversation in the current directory. Task will fail in a new workspace with no conversation/session to continue"
-  default     = false
+  description = "Automatically continue existing sessions on workspace restart. When true, resumes existing conversation if found, otherwise runs prompt or starts new session. When false, always starts fresh (ignores existing sessions)."
+  default     = true
 }
 
 variable "dangerously_skip_permissions" {

registry/coder/modules/claude-code/scripts/start.sh

@@ -64,37 +64,70 @@ function validate_claude_installation() {
   fi
 }
 
-ARGS=()
+TASK_SESSION_ID="cd32e253-ca16-4fd3-9825-d837e74ae3c2"
 
-function build_claude_args() {
-  if [ -n "$ARG_MODEL" ]; then
-    ARGS+=(--model "$ARG_MODEL")
+task_session_exists() {
+  if find "$HOME/.claude" -type f -name "*${TASK_SESSION_ID}*" 2> /dev/null | grep -q .; then
+    return 0
+  else
+    return 1
   fi
+}
 
-  if [ -n "$ARG_RESUME_SESSION_ID" ]; then
-    ARGS+=(--resume "$ARG_RESUME_SESSION_ID")
-  fi
+ARGS=()
 
-  if [ "$ARG_CONTINUE" = "true" ]; then
-    ARGS+=(--continue)
+function start_agentapi() {
+  mkdir -p "$ARG_WORKDIR"
+  cd "$ARG_WORKDIR"
+
+  if [ -n "$ARG_MODEL" ]; then
+    ARGS+=(--model "$ARG_MODEL")
   fi
 
   if [ -n "$ARG_PERMISSION_MODE" ]; then
     ARGS+=(--permission-mode "$ARG_PERMISSION_MODE")
   fi
 
-}
-
-function start_agentapi() {
-  mkdir -p "$ARG_WORKDIR"
-  cd "$ARG_WORKDIR"
-  if [ -n "$ARG_AI_PROMPT" ]; then
-    ARGS+=(--dangerously-skip-permissions "$ARG_AI_PROMPT")
-  else
-    if [ -n "$ARG_DANGEROUSLY_SKIP_PERMISSIONS" ]; then
+  if [ -n "$ARG_RESUME_SESSION_ID" ]; then
+    echo "Using explicit resume_session_id: $ARG_RESUME_SESSION_ID"
+    ARGS+=(--resume "$ARG_RESUME_SESSION_ID")
+    if [ "$ARG_DANGEROUSLY_SKIP_PERMISSIONS" = "true" ]; then
       ARGS+=(--dangerously-skip-permissions)
     fi
+  elif [ "$ARG_CONTINUE" = "true" ]; then
+    if task_session_exists; then
+      echo "Task session detected (ID: $TASK_SESSION_ID)"
+      ARGS+=(--resume "$TASK_SESSION_ID")
+      if [ "$ARG_DANGEROUSLY_SKIP_PERMISSIONS" = "true" ]; then
+        ARGS+=(--dangerously-skip-permissions)
+      fi
+      echo "Resuming existing task session"
+    else
+      echo "No existing task session found"
+      ARGS+=(--session-id "$TASK_SESSION_ID")
+      if [ -n "$ARG_AI_PROMPT" ]; then
+        ARGS+=(--dangerously-skip-permissions "$ARG_AI_PROMPT")
+        echo "Starting new task session with prompt"
+      else
+        if [ "$ARG_DANGEROUSLY_SKIP_PERMISSIONS" = "true" ]; then
+          ARGS+=(--dangerously-skip-permissions)
+        fi
+        echo "Starting new task session"
+      fi
+    fi
+  else
+    echo "Continue disabled, starting fresh session"
+    if [ -n "$ARG_AI_PROMPT" ]; then
+      ARGS+=(--dangerously-skip-permissions "$ARG_AI_PROMPT")
+      echo "Starting new session with prompt"
+    else
+      if [ "$ARG_DANGEROUSLY_SKIP_PERMISSIONS" = "true" ]; then
+        ARGS+=(--dangerously-skip-permissions)
+      fi
+      echo "Starting claude code session"
+    fi
   fi
+
   printf "Running claude code with args: %s\n" "$(printf '%q ' "${ARGS[@]}")"
 
   if [ "${ARG_ENABLE_BOUNDARY:-false}" = "true" ]; then
@@ -140,5 +173,4 @@ function start_agentapi() {
 }
 
 validate_claude_installation
-build_claude_args
 start_agentapi