Loading ToolBench
Model Context Protocol server for Playwright browser automation and API testing
30 tools with mixed quality. Strengths: all tools have descriptions (10-200 chars, mostly adequate); input schemas present with type definitions for most parameters. Critical weaknesses: 18 tools lack descriptions under 50 chars (e.g., 'Click an element on the page' for playwright_click is generic); no output schemas documented anywhere; error handling is absent (no recovery guidance, no categorization); tool names use verb_noun pattern correctly but lack clarity on side effects (e.g., playwright_navigate vs playwright_click both modify state but descriptions don't say so); HTTP request tools (GET/POST/PUT/PATCH/DELETE) expose bearer tokens as parameters, violating secret-injection pattern; no tool annotations (readOnlyHint, destructiveHint, idempotentHint) despite clear risk levels assigned. Composition: tools are single-purpose (good), but codegen session tools (start/end/get/clear) form a stateful workflow that should be documented as a sequence. Parameter quality: most have descriptions, but 'timeout', 'waitUntil', 'device' lack format/constraint details; 'filePath' and 'outputPath' don't specify absolute vs relative or validation rules.
Clear a code generation session without generating a test
End a code generation session and generate the test file
Get information about a code generation session
Click an element on the page
Click an element and switch to the newly opened tab
Close the browser and release all resources
Retrieve console logs from the browser with filtering options
Bearer tokens exposed as tool parameters in HTTP request tools (playwright_get, playwright_post, playwright_put, playwright_patch, playwright_delete). Tokens in parameters are logged and enter LLM context, violating secret-injection pattern.
No output schemas documented for any tool. LLMs cannot plan downstream calls or extract required fields. Codegen tools return sessionId but structure is undocumented; screenshot tool returns base64 but format/size limits unknown.
18 tools have generic descriptions under 50 chars (e.g., 'Click an element on the page', 'Hover an element on the page'). These lack context for LLM selection and do not state side effects or prerequisites.
Inferred effective spec: <=2025-11-25.
| Scored | Grade | Overall | Spec posture | Rubric |
|---|---|---|---|---|
| 2026-09-23 | D | 58 | <=2025-11-25 | v2 |
Perform an HTTP DELETE request
Drag an element on the page
Execute JavaScript in the browser console
fill out an input field
Perform an HTTP GET request
Get visible HTML content from the current page
Get visible text content from the current page
Navigate back to the previous page
Navigate forward to the next page
Hover an element on the page
Click an element in an iframe on the page
Fill an element in an iframe on the page
Navigate to a URL
Perform an HTTP PATCH request
Perform an HTTP POST request
Press a keyboard key
Perform an HTTP PUT request
Resize the browser viewport using manual dimensions or device presets. Supports 143+ device presets including iPhone, iPad, Android devices, and desktop browsers with proper user-agent and touch emulation.
Save the current page as a PDF file
Take a screenshot of the current page or a specific element
Select an element on the page with Select tag
Upload a file to an input[type='file'] element on the page
Start a new code generation session to record Playwright actions
No tool annotations (readOnlyHint, destructiveHint, idempotentHint) despite clear risk levels assigned (READ_ONLY, WRITE, DESTRUCTIVE). LLMs cannot infer safety properties without explicit hints.
No error handling or recovery guidance. Tools fail silently or return raw errors. E.g., 'selector not found' should suggest 'Call playwright_get_visible_html to inspect page structure' or 'Invalid file path' should explain absolute vs relative requirements.