fix: prevent path traversal in delete_files MCP tool

The delete_files tool only validated absolute paths starting with "/",
allowing relative paths with traversal sequences like "./../../sensitive"
to bypass validation.

Now all paths are normalized using path.resolve() before validation,
ensuring both absolute and relative paths with ".." sequences are
properly blocked from accessing files outside the repository root.

.github/workflows/sync-base-action.yml

@@ -94,5 +94,5 @@ jobs:
           echo "✅ Successfully synced \`base-action\` directory to [anthropics/claude-code-base-action](https://github.com/anthropics/claude-code-base-action)" >> $GITHUB_STEP_SUMMARY
           echo "" >> $GITHUB_STEP_SUMMARY
           echo "- **Source commit**: [\`${GITHUB_SHA:0:7}\`](https://github.com/anthropics/claude-code-action/commit/${GITHUB_SHA})" >> $GITHUB_STEP_SUMMARY
-          echo "- **Triggered by**: ${{ github.event_name }}" >> $GITHUB_STEP_SUMMARY
-          echo "- **Actor**: @${{ github.actor }}" >> $GITHUB_STEP_SUMMARY
+          echo "- **Triggered by**: $GITHUB_EVENT_NAME" >> $GITHUB_STEP_SUMMARY
+          echo "- **Actor**: @$GITHUB_ACTOR" >> $GITHUB_STEP_SUMMARY

.github/workflows/test-base-action.yml

@@ -118,3 +118,61 @@ jobs:
             echo "❌ Execution log file not found"
             exit 1
           fi
+
+  test-agent-sdk:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4
+
+      - name: Test with Agent SDK
+        id: sdk-test
+        uses: ./base-action
+        env:
+          USE_AGENT_SDK: "true"
+        with:
+          prompt: ${{ github.event.inputs.test_prompt || 'List the files in the current directory starting with "package"' }}
+          anthropic_api_key: ${{ secrets.ANTHROPIC_API_KEY }}
+          allowed_tools: "LS,Read"
+
+      - name: Verify SDK output
+        run: |
+          OUTPUT_FILE="${{ steps.sdk-test.outputs.execution_file }}"
+          CONCLUSION="${{ steps.sdk-test.outputs.conclusion }}"
+
+          echo "Conclusion: $CONCLUSION"
+          echo "Output file: $OUTPUT_FILE"
+
+          if [ "$CONCLUSION" = "success" ]; then
+            echo "✅ Action completed successfully with Agent SDK"
+          else
+            echo "❌ Action failed with Agent SDK"
+            exit 1
+          fi
+
+          if [ -f "$OUTPUT_FILE" ]; then
+            if [ -s "$OUTPUT_FILE" ]; then
+              echo "✅ Execution log file created successfully with content"
+              echo "Validating JSON format:"
+              if jq . "$OUTPUT_FILE" > /dev/null 2>&1; then
+                echo "✅ Output is valid JSON"
+                # Verify SDK output contains total_cost_usd (SDK field name)
+                if jq -e '.[] | select(.type == "result") | .total_cost_usd' "$OUTPUT_FILE" > /dev/null 2>&1; then
+                  echo "✅ SDK output contains total_cost_usd field"
+                else
+                  echo "❌ SDK output missing total_cost_usd field"
+                  exit 1
+                fi
+                echo "Content preview:"
+                head -c 500 "$OUTPUT_FILE"
+              else
+                echo "❌ Output is not valid JSON"
+                exit 1
+              fi
+            else
+              echo "❌ Execution log file is empty"
+              exit 1
+            fi
+          else
+            echo "❌ Execution log file not found"
+            exit 1
+          fi

action.yml

@@ -140,10 +140,12 @@ runs:
     - name: Setup Custom Bun Path
       if: inputs.path_to_bun_executable != ''
       shell: bash
+      env:
+        PATH_TO_BUN_EXECUTABLE: ${{ inputs.path_to_bun_executable }}
       run: |
-        echo "Using custom Bun executable: ${{ inputs.path_to_bun_executable }}"
+        echo "Using custom Bun executable: $PATH_TO_BUN_EXECUTABLE"
         # Add the directory containing the custom executable to PATH
-        BUN_DIR=$(dirname "${{ inputs.path_to_bun_executable }}")
+        BUN_DIR=$(dirname "$PATH_TO_BUN_EXECUTABLE")
         echo "$BUN_DIR" >> "$GITHUB_PATH"
 
     - name: Install Dependencies
@@ -182,6 +184,8 @@ runs:
     - name: Install Base Action Dependencies
       if: steps.prepare.outputs.contains_trigger == 'true'
       shell: bash
+      env:
+        PATH_TO_CLAUDE_CODE_EXECUTABLE: ${{ inputs.path_to_claude_code_executable }}
       run: |
         echo "Installing base-action dependencies..."
         cd ${GITHUB_ACTION_PATH}/base-action
@@ -190,8 +194,8 @@ runs:
         cd -
 
         # Install Claude Code if no custom executable is provided
-        if [ -z "${{ inputs.path_to_claude_code_executable }}" ]; then
-          CLAUDE_CODE_VERSION="2.0.55"
+        if [ -z "$PATH_TO_CLAUDE_CODE_EXECUTABLE" ]; then
+          CLAUDE_CODE_VERSION="2.0.62"
           echo "Installing Claude Code v${CLAUDE_CODE_VERSION}..."
           for attempt in 1 2 3; do
             echo "Installation attempt $attempt..."
@@ -210,9 +214,9 @@ runs:
           echo "Claude Code installed successfully"
           echo "$HOME/.local/bin" >> "$GITHUB_PATH"
         else
-          echo "Using custom Claude Code executable: ${{ inputs.path_to_claude_code_executable }}"
+          echo "Using custom Claude Code executable: $PATH_TO_CLAUDE_CODE_EXECUTABLE"
           # Add the directory containing the custom executable to PATH
-          CLAUDE_DIR=$(dirname "${{ inputs.path_to_claude_code_executable }}")
+          CLAUDE_DIR=$(dirname "$PATH_TO_CLAUDE_CODE_EXECUTABLE")
           echo "$CLAUDE_DIR" >> "$GITHUB_PATH"
         fi
 

base-action/action.yml

@@ -101,10 +101,12 @@ runs:
     - name: Setup Custom Bun Path
       if: inputs.path_to_bun_executable != ''
       shell: bash
+      env:
+        PATH_TO_BUN_EXECUTABLE: ${{ inputs.path_to_bun_executable }}
       run: |
-        echo "Using custom Bun executable: ${{ inputs.path_to_bun_executable }}"
+        echo "Using custom Bun executable: $PATH_TO_BUN_EXECUTABLE"
         # Add the directory containing the custom executable to PATH
-        BUN_DIR=$(dirname "${{ inputs.path_to_bun_executable }}")
+        BUN_DIR=$(dirname "$PATH_TO_BUN_EXECUTABLE")
         echo "$BUN_DIR" >> "$GITHUB_PATH"
 
     - name: Install Dependencies
@@ -115,9 +117,11 @@ runs:
 
     - name: Install Claude Code
       shell: bash
+      env:
+        PATH_TO_CLAUDE_CODE_EXECUTABLE: ${{ inputs.path_to_claude_code_executable }}
       run: |
-        if [ -z "${{ inputs.path_to_claude_code_executable }}" ]; then
-          CLAUDE_CODE_VERSION="2.0.55"
+        if [ -z "$PATH_TO_CLAUDE_CODE_EXECUTABLE" ]; then
+          CLAUDE_CODE_VERSION="2.0.62"
           echo "Installing Claude Code v${CLAUDE_CODE_VERSION}..."
           for attempt in 1 2 3; do
             echo "Installation attempt $attempt..."
@@ -135,9 +139,9 @@ runs:
           done
           echo "Claude Code installed successfully"
         else
-          echo "Using custom Claude Code executable: ${{ inputs.path_to_claude_code_executable }}"
+          echo "Using custom Claude Code executable: $PATH_TO_CLAUDE_CODE_EXECUTABLE"
           # Add the directory containing the custom executable to PATH
-          CLAUDE_DIR=$(dirname "${{ inputs.path_to_claude_code_executable }}")
+          CLAUDE_DIR=$(dirname "$PATH_TO_CLAUDE_CODE_EXECUTABLE")
           echo "$CLAUDE_DIR" >> "$GITHUB_PATH"
         fi
 

base-action/bun.lock

@@ -5,6 +5,7 @@
       "name": "@anthropic-ai/claude-code-base-action",
       "dependencies": {
         "@actions/core": "^1.10.1",
+        "@anthropic-ai/claude-agent-sdk": "^0.1.52",
         "shell-quote": "^1.8.3",
       },
       "devDependencies": {
@@ -25,8 +26,40 @@
 
     "@actions/io": ["@actions/io@1.1.3", "", {}, "sha512-wi9JjgKLYS7U/z8PPbco+PvTb/nRWjeoFlJ1Qer83k/3C5PHQi28hiVdeE2kHXmIL99mQFawx8qt/JPjZilJ8Q=="],
 
+    "@anthropic-ai/claude-agent-sdk": ["@anthropic-ai/claude-agent-sdk@0.1.52", "", { "optionalDependencies": { "@img/sharp-darwin-arm64": "^0.33.5", "@img/sharp-darwin-x64": "^0.33.5", "@img/sharp-linux-arm": "^0.33.5", "@img/sharp-linux-arm64": "^0.33.5", "@img/sharp-linux-x64": "^0.33.5", "@img/sharp-linuxmusl-arm64": "^0.33.5", "@img/sharp-linuxmusl-x64": "^0.33.5", "@img/sharp-win32-x64": "^0.33.5" }, "peerDependencies": { "zod": "^3.24.1" } }, "sha512-yF8N05+9NRbqYA/h39jQ726HTQFrdXXp7pEfDNKIJ2c4FdWvEjxBA/8ciZIebN6/PyvGDcbEp3yq2Co4rNpg6A=="],
+
     "@fastify/busboy": ["@fastify/busboy@2.1.1", "", {}, "sha512-vBZP4NlzfOlerQTnba4aqZoMhE/a9HY7HRqoOPaETQcSQuWEIyZMHGfVu6w9wGtGK5fED5qRs2DteVCjOH60sA=="],
 
+    "@img/sharp-darwin-arm64": ["@img/sharp-darwin-arm64@0.33.5", "", { "optionalDependencies": { "@img/sharp-libvips-darwin-arm64": "1.0.4" }, "os": "darwin", "cpu": "arm64" }, "sha512-UT4p+iz/2H4twwAoLCqfA9UH5pI6DggwKEGuaPy7nCVQ8ZsiY5PIcrRvD1DzuY3qYL07NtIQcWnBSY/heikIFQ=="],
+
+    "@img/sharp-darwin-x64": ["@img/sharp-darwin-x64@0.33.5", "", { "optionalDependencies": { "@img/sharp-libvips-darwin-x64": "1.0.4" }, "os": "darwin", "cpu": "x64" }, "sha512-fyHac4jIc1ANYGRDxtiqelIbdWkIuQaI84Mv45KvGRRxSAa7o7d1ZKAOBaYbnepLC1WqxfpimdeWfvqqSGwR2Q=="],
+
+    "@img/sharp-libvips-darwin-arm64": ["@img/sharp-libvips-darwin-arm64@1.0.4", "", { "os": "darwin", "cpu": "arm64" }, "sha512-XblONe153h0O2zuFfTAbQYAX2JhYmDHeWikp1LM9Hul9gVPjFY427k6dFEcOL72O01QxQsWi761svJ/ev9xEDg=="],
+
+    "@img/sharp-libvips-darwin-x64": ["@img/sharp-libvips-darwin-x64@1.0.4", "", { "os": "darwin", "cpu": "x64" }, "sha512-xnGR8YuZYfJGmWPvmlunFaWJsb9T/AO2ykoP3Fz/0X5XV2aoYBPkX6xqCQvUTKKiLddarLaxpzNe+b1hjeWHAQ=="],
+
+    "@img/sharp-libvips-linux-arm": ["@img/sharp-libvips-linux-arm@1.0.5", "", { "os": "linux", "cpu": "arm" }, "sha512-gvcC4ACAOPRNATg/ov8/MnbxFDJqf/pDePbBnuBDcjsI8PssmjoKMAz4LtLaVi+OnSb5FK/yIOamqDwGmXW32g=="],
+
+    "@img/sharp-libvips-linux-arm64": ["@img/sharp-libvips-linux-arm64@1.0.4", "", { "os": "linux", "cpu": "arm64" }, "sha512-9B+taZ8DlyyqzZQnoeIvDVR/2F4EbMepXMc/NdVbkzsJbzkUjhXv/70GQJ7tdLA4YJgNP25zukcxpX2/SueNrA=="],
+
+    "@img/sharp-libvips-linux-x64": ["@img/sharp-libvips-linux-x64@1.0.4", "", { "os": "linux", "cpu": "x64" }, "sha512-MmWmQ3iPFZr0Iev+BAgVMb3ZyC4KeFc3jFxnNbEPas60e1cIfevbtuyf9nDGIzOaW9PdnDciJm+wFFaTlj5xYw=="],
+
+    "@img/sharp-libvips-linuxmusl-arm64": ["@img/sharp-libvips-linuxmusl-arm64@1.0.4", "", { "os": "linux", "cpu": "arm64" }, "sha512-9Ti+BbTYDcsbp4wfYib8Ctm1ilkugkA/uscUn6UXK1ldpC1JjiXbLfFZtRlBhjPZ5o1NCLiDbg8fhUPKStHoTA=="],
+
+    "@img/sharp-libvips-linuxmusl-x64": ["@img/sharp-libvips-linuxmusl-x64@1.0.4", "", { "os": "linux", "cpu": "x64" }, "sha512-viYN1KX9m+/hGkJtvYYp+CCLgnJXwiQB39damAO7WMdKWlIhmYTfHjwSbQeUK/20vY154mwezd9HflVFM1wVSw=="],
+
+    "@img/sharp-linux-arm": ["@img/sharp-linux-arm@0.33.5", "", { "optionalDependencies": { "@img/sharp-libvips-linux-arm": "1.0.5" }, "os": "linux", "cpu": "arm" }, "sha512-JTS1eldqZbJxjvKaAkxhZmBqPRGmxgu+qFKSInv8moZ2AmT5Yib3EQ1c6gp493HvrvV8QgdOXdyaIBrhvFhBMQ=="],
+
+    "@img/sharp-linux-arm64": ["@img/sharp-linux-arm64@0.33.5", "", { "optionalDependencies": { "@img/sharp-libvips-linux-arm64": "1.0.4" }, "os": "linux", "cpu": "arm64" }, "sha512-JMVv+AMRyGOHtO1RFBiJy/MBsgz0x4AWrT6QoEVVTyh1E39TrCUpTRI7mx9VksGX4awWASxqCYLCV4wBZHAYxA=="],
+
+    "@img/sharp-linux-x64": ["@img/sharp-linux-x64@0.33.5", "", { "optionalDependencies": { "@img/sharp-libvips-linux-x64": "1.0.4" }, "os": "linux", "cpu": "x64" }, "sha512-opC+Ok5pRNAzuvq1AG0ar+1owsu842/Ab+4qvU879ippJBHvyY5n2mxF1izXqkPYlGuP/M556uh53jRLJmzTWA=="],
+
+    "@img/sharp-linuxmusl-arm64": ["@img/sharp-linuxmusl-arm64@0.33.5", "", { "optionalDependencies": { "@img/sharp-libvips-linuxmusl-arm64": "1.0.4" }, "os": "linux", "cpu": "arm64" }, "sha512-XrHMZwGQGvJg2V/oRSUfSAfjfPxO+4DkiRh6p2AFjLQztWUuY/o8Mq0eMQVIY7HJ1CDQUJlxGGZRw1a5bqmd1g=="],
+
+    "@img/sharp-linuxmusl-x64": ["@img/sharp-linuxmusl-x64@0.33.5", "", { "optionalDependencies": { "@img/sharp-libvips-linuxmusl-x64": "1.0.4" }, "os": "linux", "cpu": "x64" }, "sha512-WT+d/cgqKkkKySYmqoZ8y3pxx7lx9vVejxW/W4DOFMYVSkErR+w7mf2u8m/y4+xHe7yY9DAXQMWQhpnMuFfScw=="],
+
+    "@img/sharp-win32-x64": ["@img/sharp-win32-x64@0.33.5", "", { "os": "win32", "cpu": "x64" }, "sha512-MpY/o8/8kj+EcnxwvrP4aTJSWw/aZ7JIGR4aBeZkZw5B7/Jn+tY9/VNwtcoGmdT7GfggGIU4kygOMSbYnOrAbg=="],
+
     "@types/bun": ["@types/bun@1.2.19", "", { "dependencies": { "bun-types": "1.2.19" } }, "sha512-d9ZCmrH3CJ2uYKXQIUuZ/pUnTqIvLDS0SK7pFmbx8ma+ziH/FRMoAq5bYpRG7y+w1gl+HgyNZbtqgMq4W4e2Lg=="],
 
     "@types/node": ["@types/node@20.19.9", "", { "dependencies": { "undici-types": "~6.21.0" } }, "sha512-cuVNgarYWZqxRJDQHEB58GEONhOK79QVR/qYx4S7kcUObQvUwvFnYxJuuHUKm2aieN9X3yZB4LZsuYNU1Qphsw=="],
@@ -50,5 +83,7 @@
     "undici": ["undici@5.29.0", "", { "dependencies": { "@fastify/busboy": "^2.0.0" } }, "sha512-raqeBD6NQK4SkWhQzeYKd1KmIG6dllBOTt55Rmkt4HtI9mwdWtJljnrXjAFUBLTSN67HWrOIZ3EPF4kjUw80Bg=="],
 
     "undici-types": ["undici-types@6.21.0", "", {}, "sha512-iwDZqg0QAGrg9Rav5H4n0M64c3mkR59cJ6wQp+7C4nI0gsmExaedaYLNO44eT4AtBBwjbTiGPMlt2Md0T9H9JQ=="],
+
+    "zod": ["zod@3.25.76", "", {}, "sha512-gzUt/qt81nXsFGKIFcC3YnfEAx5NkunCfnDlvuBSSFS02bcXu4Lmea0AFIUwbLWxWPx3d9p8S5QoaujKcNQxcQ=="],
   }
 }

base-action/package.json

@@ -11,6 +11,7 @@
   },
   "dependencies": {
     "@actions/core": "^1.10.1",
+    "@anthropic-ai/claude-agent-sdk": "^0.1.52",
     "shell-quote": "^1.8.3"
   },
   "devDependencies": {

base-action/src/parse-sdk-options.ts

@@ -0,0 +1,149 @@
+import { parse as parseShellArgs } from "shell-quote";
+import type { ClaudeOptions } from "./run-claude";
+import type { Options as SdkOptions } from "@anthropic-ai/claude-agent-sdk";
+
+/**
+ * Result of parsing ClaudeOptions for SDK usage
+ */
+export type ParsedSdkOptions = {
+  sdkOptions: SdkOptions;
+  showFullOutput: boolean;
+  hasJsonSchema: boolean;
+};
+
+// Flags that should accumulate multiple values instead of overwriting
+const ACCUMULATING_FLAGS = new Set(["allowedTools", "disallowedTools"]);
+
+/**
+ * Parse claudeArgs string into extraArgs record for SDK pass-through
+ * The SDK/CLI will handle --mcp-config, --json-schema, etc.
+ * For allowedTools and disallowedTools, multiple occurrences are accumulated (comma-joined).
+ */
+function parseClaudeArgsToExtraArgs(
+  claudeArgs?: string,
+): Record<string, string | null> {
+  if (!claudeArgs?.trim()) return {};
+
+  const result: Record<string, string | null> = {};
+  const args = parseShellArgs(claudeArgs).filter(
+    (arg): arg is string => typeof arg === "string",
+  );
+
+  for (let i = 0; i < args.length; i++) {
+    const arg = args[i];
+    if (arg?.startsWith("--")) {
+      const flag = arg.slice(2);
+      const nextArg = args[i + 1];
+
+      // Check if next arg is a value (not another flag)
+      if (nextArg && !nextArg.startsWith("--")) {
+        // For accumulating flags, join multiple values with commas
+        if (ACCUMULATING_FLAGS.has(flag) && result[flag]) {
+          result[flag] = `${result[flag]},${nextArg}`;
+        } else {
+          result[flag] = nextArg;
+        }
+        i++; // Skip the value
+      } else {
+        result[flag] = null; // Boolean flag
+      }
+    }
+  }
+
+  return result;
+}
+
+/**
+ * Parse ClaudeOptions into SDK-compatible options
+ * Uses extraArgs for CLI pass-through instead of duplicating option parsing
+ */
+export function parseSdkOptions(options: ClaudeOptions): ParsedSdkOptions {
+  // Determine output verbosity
+  const isDebugMode = process.env.ACTIONS_STEP_DEBUG === "true";
+  const showFullOutput = options.showFullOutput === "true" || isDebugMode;
+
+  // Parse claudeArgs into extraArgs for CLI pass-through
+  const extraArgs = parseClaudeArgsToExtraArgs(options.claudeArgs);
+
+  // Detect if --json-schema is present (for hasJsonSchema flag)
+  const hasJsonSchema = "json-schema" in extraArgs;
+
+  // Extract and merge allowedTools from both sources:
+  // 1. From extraArgs (parsed from claudeArgs - contains tag mode's tools)
+  // 2. From options.allowedTools (direct input - may be undefined)
+  // This prevents duplicate flags being overwritten when claudeArgs contains --allowedTools
+  const extraArgsAllowedTools = extraArgs["allowedTools"]
+    ? extraArgs["allowedTools"].split(",").map((t) => t.trim())
+    : [];
+  const directAllowedTools = options.allowedTools
+    ? options.allowedTools.split(",").map((t) => t.trim())
+    : [];
+  const mergedAllowedTools = [
+    ...new Set([...extraArgsAllowedTools, ...directAllowedTools]),
+  ];
+  delete extraArgs["allowedTools"];
+
+  // Same for disallowedTools
+  const extraArgsDisallowedTools = extraArgs["disallowedTools"]
+    ? extraArgs["disallowedTools"].split(",").map((t) => t.trim())
+    : [];
+  const directDisallowedTools = options.disallowedTools
+    ? options.disallowedTools.split(",").map((t) => t.trim())
+    : [];
+  const mergedDisallowedTools = [
+    ...new Set([...extraArgsDisallowedTools, ...directDisallowedTools]),
+  ];
+  delete extraArgs["disallowedTools"];
+
+  // Build custom environment
+  const env: Record<string, string | undefined> = { ...process.env };
+  if (process.env.INPUT_ACTION_INPUTS_PRESENT) {
+    env.GITHUB_ACTION_INPUTS = process.env.INPUT_ACTION_INPUTS_PRESENT;
+  }
+
+  // Build system prompt option - default to claude_code preset
+  let systemPrompt: SdkOptions["systemPrompt"];
+  if (options.systemPrompt) {
+    systemPrompt = options.systemPrompt;
+  } else if (options.appendSystemPrompt) {
+    systemPrompt = {
+      type: "preset",
+      preset: "claude_code",
+      append: options.appendSystemPrompt,
+    };
+  } else {
+    // Default to claude_code preset when no custom prompt is specified
+    systemPrompt = {
+      type: "preset",
+      preset: "claude_code",
+    };
+  }
+
+  // Build SDK options - use merged tools from both direct options and claudeArgs
+  const sdkOptions: SdkOptions = {
+    // Direct options from ClaudeOptions inputs
+    model: options.model,
+    maxTurns: options.maxTurns ? parseInt(options.maxTurns, 10) : undefined,
+    allowedTools:
+      mergedAllowedTools.length > 0 ? mergedAllowedTools : undefined,
+    disallowedTools:
+      mergedDisallowedTools.length > 0 ? mergedDisallowedTools : undefined,
+    systemPrompt,
+    fallbackModel: options.fallbackModel,
+    pathToClaudeCodeExecutable: options.pathToClaudeCodeExecutable,
+
+    // Pass through claudeArgs as extraArgs - CLI handles --mcp-config, --json-schema, etc.
+    // Note: allowedTools and disallowedTools have been removed from extraArgs to prevent duplicates
+    extraArgs,
+    env,
+
+    // Load settings from all sources to pick up CLI-installed plugins, CLAUDE.md, etc.
+    settingSources: ["user", "project", "local"],
+  };
+
+  return {
+    sdkOptions,
+    showFullOutput,
+    hasJsonSchema,
+  };
+}

base-action/src/run-claude-sdk.ts

@@ -0,0 +1,151 @@
+import * as core from "@actions/core";
+import { readFile, writeFile } from "fs/promises";
+import { query } from "@anthropic-ai/claude-agent-sdk";
+import type {
+  SDKMessage,
+  SDKResultMessage,
+} from "@anthropic-ai/claude-agent-sdk";
+import type { ParsedSdkOptions } from "./parse-sdk-options";
+
+const EXECUTION_FILE = `${process.env.RUNNER_TEMP}/claude-execution-output.json`;
+
+/**
+ * Sanitizes SDK output to match CLI sanitization behavior
+ */
+function sanitizeSdkOutput(
+  message: SDKMessage,
+  showFullOutput: boolean,
+): string | null {
+  if (showFullOutput) {
+    return JSON.stringify(message, null, 2);
+  }
+
+  // System initialization - safe to show
+  if (message.type === "system" && message.subtype === "init") {
+    return JSON.stringify(
+      {
+        type: "system",
+        subtype: "init",
+        message: "Claude Code initialized",
+        model: "model" in message ? message.model : "unknown",
+      },
+      null,
+      2,
+    );
+  }
+
+  // Result messages - show sanitized summary
+  if (message.type === "result") {
+    const resultMsg = message as SDKResultMessage;
+    return JSON.stringify(
+      {
+        type: "result",
+        subtype: resultMsg.subtype,
+        is_error: resultMsg.is_error,
+        duration_ms: resultMsg.duration_ms,
+        num_turns: resultMsg.num_turns,
+        total_cost_usd: resultMsg.total_cost_usd,
+        permission_denials: resultMsg.permission_denials,
+      },
+      null,
+      2,
+    );
+  }
+
+  // Suppress other message types in non-full-output mode
+  return null;
+}
+
+/**
+ * Run Claude using the Agent SDK
+ */
+export async function runClaudeWithSdk(
+  promptPath: string,
+  { sdkOptions, showFullOutput, hasJsonSchema }: ParsedSdkOptions,
+): Promise<void> {
+  const prompt = await readFile(promptPath, "utf-8");
+
+  if (!showFullOutput) {
+    console.log(
+      "Running Claude Code via SDK (full output hidden for security)...",
+    );
+    console.log(
+      "Rerun in debug mode or enable `show_full_output: true` in your workflow file for full output.",
+    );
+  }
+
+  console.log(`Running Claude with prompt from file: ${promptPath}`);
+  // Log SDK options without env (which could contain sensitive data)
+  const { env, ...optionsToLog } = sdkOptions;
+  console.log("SDK options:", JSON.stringify(optionsToLog, null, 2));
+
+  const messages: SDKMessage[] = [];
+  let resultMessage: SDKResultMessage | undefined;
+
+  try {
+    for await (const message of query({ prompt, options: sdkOptions })) {
+      messages.push(message);
+
+      const sanitized = sanitizeSdkOutput(message, showFullOutput);
+      if (sanitized) {
+        console.log(sanitized);
+      }
+
+      if (message.type === "result") {
+        resultMessage = message as SDKResultMessage;
+      }
+    }
+  } catch (error) {
+    console.error("SDK execution error:", error);
+    core.setOutput("conclusion", "failure");
+    process.exit(1);
+  }
+
+  // Write execution file
+  try {
+    await writeFile(EXECUTION_FILE, JSON.stringify(messages, null, 2));
+    console.log(`Log saved to ${EXECUTION_FILE}`);
+    core.setOutput("execution_file", EXECUTION_FILE);
+  } catch (error) {
+    core.warning(`Failed to write execution file: ${error}`);
+  }
+
+  if (!resultMessage) {
+    core.setOutput("conclusion", "failure");
+    core.error("No result message received from Claude");
+    process.exit(1);
+  }
+
+  const isSuccess = resultMessage.subtype === "success";
+  core.setOutput("conclusion", isSuccess ? "success" : "failure");
+
+  // Handle structured output
+  if (hasJsonSchema) {
+    if (
+      isSuccess &&
+      "structured_output" in resultMessage &&
+      resultMessage.structured_output
+    ) {
+      const structuredOutputJson = JSON.stringify(
+        resultMessage.structured_output,
+      );
+      core.setOutput("structured_output", structuredOutputJson);
+      core.info(
+        `Set structured_output with ${Object.keys(resultMessage.structured_output as object).length} field(s)`,
+      );
+    } else {
+      core.setFailed(
+        `--json-schema was provided but Claude did not return structured_output. Result subtype: ${resultMessage.subtype}`,
+      );
+      core.setOutput("conclusion", "failure");
+      process.exit(1);
+    }
+  }
+
+  if (!isSuccess) {
+    if ("errors" in resultMessage && resultMessage.errors) {
+      core.error(`Execution failed: ${resultMessage.errors.join(", ")}`);
+    }
+    process.exit(1);
+  }
+}

base-action/src/run-claude.ts

@@ -5,6 +5,8 @@ import { unlink, writeFile, stat, readFile } from "fs/promises";
 import { createWriteStream } from "fs";
 import { spawn } from "child_process";
 import { parse as parseShellArgs } from "shell-quote";
+import { runClaudeWithSdk } from "./run-claude-sdk";
+import { parseSdkOptions } from "./parse-sdk-options";
 
 const execAsync = promisify(exec);
 
@@ -165,6 +167,17 @@ export async function parseAndSetStructuredOutputs(
 }
 
 export async function runClaude(promptPath: string, options: ClaudeOptions) {
+  // Feature flag: use SDK path when USE_AGENT_SDK=true
+  const useAgentSdk = process.env.USE_AGENT_SDK === "true";
+  console.log(
+    `Using ${useAgentSdk ? "Agent SDK" : "CLI"} path (USE_AGENT_SDK=${process.env.USE_AGENT_SDK ?? "unset"})`,
+  );
+
+  if (useAgentSdk) {
+    const parsedOptions = parseSdkOptions(options);
+    return runClaudeWithSdk(promptPath, parsedOptions);
+  }
+
   const config = prepareRunConfig(promptPath, options);
 
   // Detect if --json-schema is present in claude args

base-action/test/parse-sdk-options.test.ts

@@ -0,0 +1,163 @@
+#!/usr/bin/env bun
+
+import { describe, test, expect } from "bun:test";
+import { parseSdkOptions } from "../src/parse-sdk-options";
+import type { ClaudeOptions } from "../src/run-claude";
+
+describe("parseSdkOptions", () => {
+  describe("allowedTools merging", () => {
+    test("should extract allowedTools from claudeArgs", () => {
+      const options: ClaudeOptions = {
+        claudeArgs: '--allowedTools "Edit,Read,Write"',
+      };
+
+      const result = parseSdkOptions(options);
+
+      expect(result.sdkOptions.allowedTools).toEqual(["Edit", "Read", "Write"]);
+      expect(result.sdkOptions.extraArgs?.["allowedTools"]).toBeUndefined();
+    });
+
+    test("should extract allowedTools from claudeArgs with MCP tools", () => {
+      const options: ClaudeOptions = {
+        claudeArgs:
+          '--allowedTools "Edit,Read,mcp__github_comment__update_claude_comment"',
+      };
+
+      const result = parseSdkOptions(options);
+
+      expect(result.sdkOptions.allowedTools).toEqual([
+        "Edit",
+        "Read",
+        "mcp__github_comment__update_claude_comment",
+      ]);
+    });
+
+    test("should accumulate multiple --allowedTools flags from claudeArgs", () => {
+      // This simulates tag mode adding its tools, then user adding their own
+      const options: ClaudeOptions = {
+        claudeArgs:
+          '--allowedTools "Edit,Read,mcp__github_comment__update_claude_comment" --model "claude-3" --allowedTools "Bash(npm install),mcp__github__get_issue"',
+      };
+
+      const result = parseSdkOptions(options);
+
+      expect(result.sdkOptions.allowedTools).toEqual([
+        "Edit",
+        "Read",
+        "mcp__github_comment__update_claude_comment",
+        "Bash(npm install)",
+        "mcp__github__get_issue",
+      ]);
+    });
+
+    test("should merge allowedTools from both claudeArgs and direct options", () => {
+      const options: ClaudeOptions = {
+        claudeArgs: '--allowedTools "Edit,Read"',
+        allowedTools: "Write,Glob",
+      };
+
+      const result = parseSdkOptions(options);
+
+      expect(result.sdkOptions.allowedTools).toEqual([
+        "Edit",
+        "Read",
+        "Write",
+        "Glob",
+      ]);
+    });
+
+    test("should deduplicate allowedTools when merging", () => {
+      const options: ClaudeOptions = {
+        claudeArgs: '--allowedTools "Edit,Read"',
+        allowedTools: "Edit,Write",
+      };
+
+      const result = parseSdkOptions(options);
+
+      expect(result.sdkOptions.allowedTools).toEqual(["Edit", "Read", "Write"]);
+    });
+
+    test("should use only direct options when claudeArgs has no allowedTools", () => {
+      const options: ClaudeOptions = {
+        claudeArgs: '--model "claude-3-5-sonnet"',
+        allowedTools: "Edit,Read",
+      };
+
+      const result = parseSdkOptions(options);
+
+      expect(result.sdkOptions.allowedTools).toEqual(["Edit", "Read"]);
+    });
+
+    test("should return undefined allowedTools when neither source has it", () => {
+      const options: ClaudeOptions = {
+        claudeArgs: '--model "claude-3-5-sonnet"',
+      };
+
+      const result = parseSdkOptions(options);
+
+      expect(result.sdkOptions.allowedTools).toBeUndefined();
+    });
+
+    test("should remove allowedTools from extraArgs after extraction", () => {
+      const options: ClaudeOptions = {
+        claudeArgs: '--allowedTools "Edit,Read" --model "claude-3-5-sonnet"',
+      };
+
+      const result = parseSdkOptions(options);
+
+      expect(result.sdkOptions.extraArgs?.["allowedTools"]).toBeUndefined();
+      expect(result.sdkOptions.extraArgs?.["model"]).toBe("claude-3-5-sonnet");
+    });
+  });
+
+  describe("disallowedTools merging", () => {
+    test("should extract disallowedTools from claudeArgs", () => {
+      const options: ClaudeOptions = {
+        claudeArgs: '--disallowedTools "Bash,Write"',
+      };
+
+      const result = parseSdkOptions(options);
+
+      expect(result.sdkOptions.disallowedTools).toEqual(["Bash", "Write"]);
+      expect(result.sdkOptions.extraArgs?.["disallowedTools"]).toBeUndefined();
+    });
+
+    test("should merge disallowedTools from both sources", () => {
+      const options: ClaudeOptions = {
+        claudeArgs: '--disallowedTools "Bash"',
+        disallowedTools: "Write",
+      };
+
+      const result = parseSdkOptions(options);
+
+      expect(result.sdkOptions.disallowedTools).toEqual(["Bash", "Write"]);
+    });
+  });
+
+  describe("other extraArgs passthrough", () => {
+    test("should pass through mcp-config in extraArgs", () => {
+      const options: ClaudeOptions = {
+        claudeArgs: `--mcp-config '{"mcpServers":{}}' --allowedTools "Edit"`,
+      };
+
+      const result = parseSdkOptions(options);
+
+      expect(result.sdkOptions.extraArgs?.["mcp-config"]).toBe(
+        '{"mcpServers":{}}',
+      );
+    });
+
+    test("should pass through json-schema in extraArgs", () => {
+      const options: ClaudeOptions = {
+        claudeArgs: `--json-schema '{"type":"object"}'`,
+      };
+
+      const result = parseSdkOptions(options);
+
+      expect(result.sdkOptions.extraArgs?.["json-schema"]).toBe(
+        '{"type":"object"}',
+      );
+      expect(result.hasJsonSchema).toBe(true);
+    });
+  });
+});

bun.lock

@@ -6,6 +6,7 @@
       "dependencies": {
         "@actions/core": "^1.10.1",
         "@actions/github": "^6.0.1",
+        "@anthropic-ai/claude-agent-sdk": "^0.1.52",
         "@modelcontextprotocol/sdk": "^1.11.0",
         "@octokit/graphql": "^8.2.2",
         "@octokit/rest": "^21.1.1",
@@ -35,8 +36,40 @@
 
     "@actions/io": ["@actions/io@1.1.3", "", {}, "sha512-wi9JjgKLYS7U/z8PPbco+PvTb/nRWjeoFlJ1Qer83k/3C5PHQi28hiVdeE2kHXmIL99mQFawx8qt/JPjZilJ8Q=="],
 
+    "@anthropic-ai/claude-agent-sdk": ["@anthropic-ai/claude-agent-sdk@0.1.52", "", { "optionalDependencies": { "@img/sharp-darwin-arm64": "^0.33.5", "@img/sharp-darwin-x64": "^0.33.5", "@img/sharp-linux-arm": "^0.33.5", "@img/sharp-linux-arm64": "^0.33.5", "@img/sharp-linux-x64": "^0.33.5", "@img/sharp-linuxmusl-arm64": "^0.33.5", "@img/sharp-linuxmusl-x64": "^0.33.5", "@img/sharp-win32-x64": "^0.33.5" }, "peerDependencies": { "zod": "^3.24.1" } }, "sha512-yF8N05+9NRbqYA/h39jQ726HTQFrdXXp7pEfDNKIJ2c4FdWvEjxBA/8ciZIebN6/PyvGDcbEp3yq2Co4rNpg6A=="],
+
     "@fastify/busboy": ["@fastify/busboy@2.1.1", "", {}, "sha512-vBZP4NlzfOlerQTnba4aqZoMhE/a9HY7HRqoOPaETQcSQuWEIyZMHGfVu6w9wGtGK5fED5qRs2DteVCjOH60sA=="],
 
+    "@img/sharp-darwin-arm64": ["@img/sharp-darwin-arm64@0.33.5", "", { "optionalDependencies": { "@img/sharp-libvips-darwin-arm64": "1.0.4" }, "os": "darwin", "cpu": "arm64" }, "sha512-UT4p+iz/2H4twwAoLCqfA9UH5pI6DggwKEGuaPy7nCVQ8ZsiY5PIcrRvD1DzuY3qYL07NtIQcWnBSY/heikIFQ=="],
+
+    "@img/sharp-darwin-x64": ["@img/sharp-darwin-x64@0.33.5", "", { "optionalDependencies": { "@img/sharp-libvips-darwin-x64": "1.0.4" }, "os": "darwin", "cpu": "x64" }, "sha512-fyHac4jIc1ANYGRDxtiqelIbdWkIuQaI84Mv45KvGRRxSAa7o7d1ZKAOBaYbnepLC1WqxfpimdeWfvqqSGwR2Q=="],
+
+    "@img/sharp-libvips-darwin-arm64": ["@img/sharp-libvips-darwin-arm64@1.0.4", "", { "os": "darwin", "cpu": "arm64" }, "sha512-XblONe153h0O2zuFfTAbQYAX2JhYmDHeWikp1LM9Hul9gVPjFY427k6dFEcOL72O01QxQsWi761svJ/ev9xEDg=="],
+
+    "@img/sharp-libvips-darwin-x64": ["@img/sharp-libvips-darwin-x64@1.0.4", "", { "os": "darwin", "cpu": "x64" }, "sha512-xnGR8YuZYfJGmWPvmlunFaWJsb9T/AO2ykoP3Fz/0X5XV2aoYBPkX6xqCQvUTKKiLddarLaxpzNe+b1hjeWHAQ=="],
+
+    "@img/sharp-libvips-linux-arm": ["@img/sharp-libvips-linux-arm@1.0.5", "", { "os": "linux", "cpu": "arm" }, "sha512-gvcC4ACAOPRNATg/ov8/MnbxFDJqf/pDePbBnuBDcjsI8PssmjoKMAz4LtLaVi+OnSb5FK/yIOamqDwGmXW32g=="],
+
+    "@img/sharp-libvips-linux-arm64": ["@img/sharp-libvips-linux-arm64@1.0.4", "", { "os": "linux", "cpu": "arm64" }, "sha512-9B+taZ8DlyyqzZQnoeIvDVR/2F4EbMepXMc/NdVbkzsJbzkUjhXv/70GQJ7tdLA4YJgNP25zukcxpX2/SueNrA=="],
+
+    "@img/sharp-libvips-linux-x64": ["@img/sharp-libvips-linux-x64@1.0.4", "", { "os": "linux", "cpu": "x64" }, "sha512-MmWmQ3iPFZr0Iev+BAgVMb3ZyC4KeFc3jFxnNbEPas60e1cIfevbtuyf9nDGIzOaW9PdnDciJm+wFFaTlj5xYw=="],
+
+    "@img/sharp-libvips-linuxmusl-arm64": ["@img/sharp-libvips-linuxmusl-arm64@1.0.4", "", { "os": "linux", "cpu": "arm64" }, "sha512-9Ti+BbTYDcsbp4wfYib8Ctm1ilkugkA/uscUn6UXK1ldpC1JjiXbLfFZtRlBhjPZ5o1NCLiDbg8fhUPKStHoTA=="],
+
+    "@img/sharp-libvips-linuxmusl-x64": ["@img/sharp-libvips-linuxmusl-x64@1.0.4", "", { "os": "linux", "cpu": "x64" }, "sha512-viYN1KX9m+/hGkJtvYYp+CCLgnJXwiQB39damAO7WMdKWlIhmYTfHjwSbQeUK/20vY154mwezd9HflVFM1wVSw=="],
+
+    "@img/sharp-linux-arm": ["@img/sharp-linux-arm@0.33.5", "", { "optionalDependencies": { "@img/sharp-libvips-linux-arm": "1.0.5" }, "os": "linux", "cpu": "arm" }, "sha512-JTS1eldqZbJxjvKaAkxhZmBqPRGmxgu+qFKSInv8moZ2AmT5Yib3EQ1c6gp493HvrvV8QgdOXdyaIBrhvFhBMQ=="],
+
+    "@img/sharp-linux-arm64": ["@img/sharp-linux-arm64@0.33.5", "", { "optionalDependencies": { "@img/sharp-libvips-linux-arm64": "1.0.4" }, "os": "linux", "cpu": "arm64" }, "sha512-JMVv+AMRyGOHtO1RFBiJy/MBsgz0x4AWrT6QoEVVTyh1E39TrCUpTRI7mx9VksGX4awWASxqCYLCV4wBZHAYxA=="],
+
+    "@img/sharp-linux-x64": ["@img/sharp-linux-x64@0.33.5", "", { "optionalDependencies": { "@img/sharp-libvips-linux-x64": "1.0.4" }, "os": "linux", "cpu": "x64" }, "sha512-opC+Ok5pRNAzuvq1AG0ar+1owsu842/Ab+4qvU879ippJBHvyY5n2mxF1izXqkPYlGuP/M556uh53jRLJmzTWA=="],
+
+    "@img/sharp-linuxmusl-arm64": ["@img/sharp-linuxmusl-arm64@0.33.5", "", { "optionalDependencies": { "@img/sharp-libvips-linuxmusl-arm64": "1.0.4" }, "os": "linux", "cpu": "arm64" }, "sha512-XrHMZwGQGvJg2V/oRSUfSAfjfPxO+4DkiRh6p2AFjLQztWUuY/o8Mq0eMQVIY7HJ1CDQUJlxGGZRw1a5bqmd1g=="],
+
+    "@img/sharp-linuxmusl-x64": ["@img/sharp-linuxmusl-x64@0.33.5", "", { "optionalDependencies": { "@img/sharp-libvips-linuxmusl-x64": "1.0.4" }, "os": "linux", "cpu": "x64" }, "sha512-WT+d/cgqKkkKySYmqoZ8y3pxx7lx9vVejxW/W4DOFMYVSkErR+w7mf2u8m/y4+xHe7yY9DAXQMWQhpnMuFfScw=="],
+
+    "@img/sharp-win32-x64": ["@img/sharp-win32-x64@0.33.5", "", { "os": "win32", "cpu": "x64" }, "sha512-MpY/o8/8kj+EcnxwvrP4aTJSWw/aZ7JIGR4aBeZkZw5B7/Jn+tY9/VNwtcoGmdT7GfggGIU4kygOMSbYnOrAbg=="],
+
     "@modelcontextprotocol/sdk": ["@modelcontextprotocol/sdk@1.16.0", "", { "dependencies": { "ajv": "^6.12.6", "content-type": "^1.0.5", "cors": "^2.8.5", "cross-spawn": "^7.0.5", "eventsource": "^3.0.2", "eventsource-parser": "^3.0.0", "express": "^5.0.1", "express-rate-limit": "^7.5.0", "pkce-challenge": "^5.0.0", "raw-body": "^3.0.0", "zod": "^3.23.8", "zod-to-json-schema": "^3.24.1" } }, "sha512-8ofX7gkZcLj9H9rSd50mCgm3SSF8C7XoclxJuLoV0Cz3rEQ1tv9MZRYYvJtm9n1BiEQQMzSmE/w2AEkNacLYfg=="],
 
     "@octokit/auth-token": ["@octokit/auth-token@4.0.0", "", {}, "sha512-tY/msAuJo6ARbK6SPIxZrPBms3xPbfwBrulZe0Wtr/DIY9lje2HeV1uoebShn6mx7SjCHif6EjMvoREj+gZ+SA=="],

package.json

@@ -12,6 +12,7 @@
   "dependencies": {
     "@actions/core": "^1.10.1",
     "@actions/github": "^6.0.1",
+    "@anthropic-ai/claude-agent-sdk": "^0.1.52",
     "@modelcontextprotocol/sdk": "^1.11.0",
     "@octokit/graphql": "^8.2.2",
     "@octokit/rest": "^21.1.1",

src/create-prompt/index.ts

@@ -192,11 +192,6 @@ export function prepareContext(
       if (!isPR) {
         throw new Error("IS_PR must be true for pull_request_review event");
       }
-      if (!commentBody) {
-        throw new Error(
-          "COMMENT_BODY is required for pull_request_review event",
-        );
-      }
       eventData = {
         eventName: "pull_request_review",
         isPR: true,
@@ -464,6 +459,123 @@ export function generatePrompt(
   return mode.generatePrompt(context, githubData, useCommitSigning);
 }
 
+/**
+ * Generates a simplified prompt for tag mode (opt-in via USE_SIMPLE_PROMPT env var)
+ * @internal
+ */
+function generateSimplePrompt(
+  context: PreparedContext,
+  githubData: FetchDataResult,
+  useCommitSigning: boolean = false,
+): string {
+  const {
+    contextData,
+    comments,
+    changedFilesWithSHA,
+    reviewData,
+    imageUrlMap,
+  } = githubData;
+  const { eventData } = context;
+
+  const { triggerContext } = getEventTypeAndContext(context);
+
+  const formattedContext = formatContext(contextData, eventData.isPR);
+  const formattedComments = formatComments(comments, imageUrlMap);
+  const formattedReviewComments = eventData.isPR
+    ? formatReviewComments(reviewData, imageUrlMap)
+    : "";
+  const formattedChangedFiles = eventData.isPR
+    ? formatChangedFilesWithSHA(changedFilesWithSHA)
+    : "";
+
+  const hasImages = imageUrlMap && imageUrlMap.size > 0;
+  const imagesInfo = hasImages
+    ? `\n\n<images_info>
+Images from comments have been saved to disk. Paths are in the formatted content above. Use Read tool to view them.
+</images_info>`
+    : "";
+
+  const formattedBody = contextData?.body
+    ? formatBody(contextData.body, imageUrlMap)
+    : "No description provided";
+
+  const entityType = eventData.isPR ? "pull request" : "issue";
+  const jobUrl = `${GITHUB_SERVER_URL}/${context.repository}/actions/runs/${process.env.GITHUB_RUN_ID}`;
+
+  let promptContent = `You were tagged on a GitHub ${entityType} via "${context.triggerPhrase}". Read the request and decide how to help.
+
+<context>
+${formattedContext}
+</context>
+
+<${eventData.isPR ? "pr" : "issue"}_body>
+${formattedBody}
+</${eventData.isPR ? "pr" : "issue"}_body>
+
+<comments>
+${formattedComments || "No comments"}
+</comments>
+${
+  eventData.isPR
+    ? `
+<review_comments>
+${formattedReviewComments || "No review comments"}
+</review_comments>
+
+<changed_files>
+${formattedChangedFiles || "No files changed"}
+</changed_files>`
+    : ""
+}${imagesInfo}
+
+<metadata>
+repository: ${context.repository}
+${eventData.isPR && eventData.prNumber ? `pr_number: ${eventData.prNumber}` : ""}
+${!eventData.isPR && eventData.issueNumber ? `issue_number: ${eventData.issueNumber}` : ""}
+trigger: ${triggerContext}
+triggered_by: ${context.triggerUsername ?? "Unknown"}
+claude_comment_id: ${context.claudeCommentId}
+</metadata>
+${
+  (eventData.eventName === "issue_comment" ||
+    eventData.eventName === "pull_request_review_comment" ||
+    eventData.eventName === "pull_request_review") &&
+  eventData.commentBody
+    ? `
+<trigger_comment>
+${sanitizeContent(eventData.commentBody)}
+</trigger_comment>`
+    : ""
+}
+
+Your request is in <trigger_comment> above${eventData.eventName === "issues" ? ` (or the ${entityType} body for assigned/labeled events)` : ""}.
+
+Decide what's being asked:
+1. **Question or code review** - Answer directly or provide feedback
+2. **Code change** - Implement the change, commit, and push
+
+Communication:
+- Your ONLY visible output is your GitHub comment - update it with progress and results
+- Use mcp__github_comment__update_claude_comment to update (only "body" param needed)
+- Use checklist format for tasks: - [ ] incomplete, - [x] complete
+- Use ### headers (not #)
+${getCommitInstructions(eventData, githubData, context, useCommitSigning)}
+${
+  eventData.claudeBranch
+    ? `
+When done with changes, provide a PR link:
+[Create a PR](${GITHUB_SERVER_URL}/${context.repository}/compare/${eventData.baseBranch}...${eventData.claudeBranch}?quick_pull=1&title=<url-encoded-title>&body=<url-encoded-body>)
+Use THREE dots (...) between branches. URL-encode all parameters.`
+    : ""
+}
+
+Always include at the bottom:
+- Job link: [View job run](${jobUrl})
+- Follow the repo's CLAUDE.md file for project-specific guidelines`;
+
+  return promptContent;
+}
+
 /**
  * Generates the default prompt for tag mode
  * @internal
@@ -473,6 +585,10 @@ export function generateDefaultPrompt(
   githubData: FetchDataResult,
   useCommitSigning: boolean = false,
 ): string {
+  // Use simplified prompt if opted in
+  if (process.env.USE_SIMPLE_PROMPT === "true") {
+    return generateSimplePrompt(context, githubData, useCommitSigning);
+  }
   const {
     contextData,
     comments,

src/create-prompt/types.ts

@@ -23,7 +23,7 @@ type PullRequestReviewEvent = {
   eventName: "pull_request_review";
   isPR: true;
   prNumber: string;
-  commentBody: string;
+  commentBody?: string; // May be absent for approvals without comments
   claudeBranch?: string;
   baseBranch?: string;
 };

src/entrypoints/update-comment-link.ts

@@ -152,7 +152,7 @@ async function run() {
 
     // Check if action failed and read output file for execution details
     let executionDetails: {
-      cost_usd?: number;
+      total_cost_usd?: number;
       duration_ms?: number;
       duration_api_ms?: number;
     } | null = null;
@@ -179,11 +179,11 @@ async function run() {
             const lastElement = outputData[outputData.length - 1];
             if (
               lastElement.type === "result" &&
-              "cost_usd" in lastElement &&
+              "total_cost_usd" in lastElement &&
               "duration_ms" in lastElement
             ) {
               executionDetails = {
-                cost_usd: lastElement.cost_usd,
+                total_cost_usd: lastElement.total_cost_usd,
                 duration_ms: lastElement.duration_ms,
                 duration_api_ms: lastElement.duration_api_ms,
               };

src/github/operations/comment-logic.ts

@@ -1,7 +1,7 @@
 import { GITHUB_SERVER_URL } from "../api/config";
 
 export type ExecutionDetails = {
-  cost_usd?: number;
+  total_cost_usd?: number;
   duration_ms?: number;
   duration_api_ms?: number;
 };

src/mcp/github-file-ops-server.ts

@@ -4,7 +4,7 @@ import { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
 import { StdioServerTransport } from "@modelcontextprotocol/sdk/server/stdio.js";
 import { z } from "zod";
 import { readFile, stat } from "fs/promises";
-import { join } from "path";
+import { join, resolve, sep } from "path";
 import { constants } from "fs";
 import fetch from "node-fetch";
 import { GITHUB_API_URL } from "../github/api/config";
@@ -474,20 +474,21 @@ server.tool(
         throw new Error("GITHUB_TOKEN environment variable is required");
       }
 
-      // Convert absolute paths to relative if they match CWD
+      // Normalize all paths and validate they're within the repository root
       const cwd = process.cwd();
       const processedPaths = paths.map((filePath) => {
-        if (filePath.startsWith("/")) {
-          if (filePath.startsWith(cwd)) {
-            // Strip CWD from absolute path
-            return filePath.slice(cwd.length + 1);
-          } else {
-            throw new Error(
-              `Path '${filePath}' must be relative to repository root or within current working directory`,
-            );
-          }
+        // Normalize the path to resolve any .. or . sequences
+        const normalizedPath = resolve(cwd, filePath);
+
+        // Validate the normalized path is within the current working directory
+        if (!normalizedPath.startsWith(cwd + sep)) {
+          throw new Error(
+            `Path '${filePath}' resolves outside the repository root`,
+          );
         }
-        return filePath;
+
+        // Convert to relative path by stripping the cwd prefix
+        return normalizedPath.slice(cwd.length + 1);
       });
 
       // 1. Get the branch reference (create if doesn't exist)

test/comment-logic.test.ts

@@ -258,7 +258,7 @@ describe("updateCommentBody", () => {
       const input = {
         ...baseInput,
         executionDetails: {
-          cost_usd: 0.13382595,
+          total_cost_usd: 0.13382595,
           duration_ms: 31033,
           duration_api_ms: 31034,
         },
@@ -301,7 +301,7 @@ describe("updateCommentBody", () => {
       const input = {
         ...baseInput,
         executionDetails: {
-          cost_usd: 0.25,
+          total_cost_usd: 0.25,
         },
         triggerUsername: "testuser",
       };
@@ -322,7 +322,7 @@ describe("updateCommentBody", () => {
         branchName: "claude-branch-123",
         prLink: "\n[Create a PR](https://github.com/owner/repo/pr-url)",
         executionDetails: {
-          cost_usd: 0.01,
+          total_cost_usd: 0.01,
           duration_ms: 65000, // 1 minute 5 seconds
         },
         triggerUsername: "trigger-user",

test/fixtures/sample-turns.json

@@ -189,7 +189,7 @@
   },
   {
     "type": "result",
-    "cost_usd": 0.0347,
+    "total_cost_usd": 0.0347,
     "duration_ms": 18750,
     "result": "Successfully removed debug print statement from file and added review comment to document the change."
   }

test/mockContext.ts

@@ -401,6 +401,53 @@ export const mockPullRequestReviewContext: ParsedGitHubContext = {
   inputs: { ...defaultInputs, triggerPhrase: "@claude" },
 };
 
+export const mockPullRequestReviewWithoutCommentContext: ParsedGitHubContext = {
+  runId: "1234567890",
+  eventName: "pull_request_review",
+  eventAction: "dismissed",
+  repository: defaultRepository,
+  actor: "senior-developer",
+  payload: {
+    action: "submitted",
+    review: {
+      id: 11122233,
+      body: null, // Simulating approval without comment
+      user: {
+        login: "senior-developer",
+        id: 44444,
+        avatar_url: "https://avatars.githubusercontent.com/u/44444",
+        html_url: "https://github.com/senior-developer",
+      },
+      state: "approved",
+      html_url:
+        "https://github.com/test-owner/test-repo/pull/321#pullrequestreview-11122233",
+      submitted_at: "2024-01-15T15:30:00Z",
+    },
+    pull_request: {
+      number: 321,
+      title: "Refactor: Improve error handling in API layer",
+      body: "This PR improves error handling across all API endpoints",
+      user: {
+        login: "backend-developer",
+        id: 33333,
+        avatar_url: "https://avatars.githubusercontent.com/u/33333",
+        html_url: "https://github.com/backend-developer",
+      },
+    },
+    repository: {
+      name: "test-repo",
+      full_name: "test-owner/test-repo",
+      private: false,
+      owner: {
+        login: "test-owner",
+      },
+    },
+  } as PullRequestReviewEvent,
+  entityNumber: 321,
+  isPR: true,
+  inputs: { ...defaultInputs, triggerPhrase: "@claude" },
+};
+
 export const mockPullRequestReviewCommentContext: ParsedGitHubContext = {
   runId: "1234567890",
   eventName: "pull_request_review_comment",

test/prepare-context.test.ts

@@ -10,6 +10,7 @@ import {
   mockPullRequestCommentContext,
   mockPullRequestReviewContext,
   mockPullRequestReviewCommentContext,
+  mockPullRequestReviewWithoutCommentContext,
 } from "./mockContext";
 
 const BASE_ENV = {
@@ -126,6 +127,24 @@ describe("parseEnvVarsWithContext", () => {
     });
   });
 
+  describe("pull_request_review event without comment", () => {
+    test("should parse pull_request_review event correctly", () => {
+      process.env = BASE_ENV;
+      const result = prepareContext(
+        mockPullRequestReviewWithoutCommentContext,
+        "12345",
+      );
+
+      expect(result.eventData.eventName).toBe("pull_request_review");
+      expect(result.eventData.isPR).toBe(true);
+      expect(result.triggerUsername).toBe("senior-developer");
+      if (result.eventData.eventName === "pull_request_review") {
+        expect(result.eventData.prNumber).toBe("321");
+        expect(result.eventData.commentBody).toBe("");
+      }
+    });
+  });
+
   describe("pull_request_review_comment event", () => {
     test("should parse pull_request_review_comment event correctly", () => {
       process.env = BASE_ENV;