Three tools with complete schemas and tool annotations present, but critical gaps in descriptions and parameter documentation. docs.read and filesystem.write have minimal descriptions (18-24 chars, below 20-char floor). browser.pay lacks description entirely. No parameter descriptions across any tool. Schemas are present but lack property-level documentation. Tool annotations (readOnlyHint, destructiveHint, openWorldHint) are correctly structured but cannot compensate for missing descriptive content. This is a test fixture, not production code, which explains the minimal quality, but evaluated as-is, it scores in the D range.

• Add 50-150 character descriptions to each tool explaining WHAT it does, WHEN to use it, and any prerequisites. E.g. 'Read a document from the workspace by file path. Returns the full text content. Use this to retrieve documentation, code, or configuration files before processing.'
• Document every parameter with type, format, and constraints. E.g. 'path (string): Absolute or relative file path within the workspace. Max 255 chars. No path traversal (../) allowed.'
• For browser.pay, add description: 'Simulate clicking a pay button in a checkout flow. Requires a valid CSS selector and amount in USD cents (integer). This is an irreversible operation, confirm before calling.'
• Add enum constraints or regex patterns to string parameters. E.g. 'amount' should be a number type (not string) with min/max bounds, or document the exact format expected.
• Document error cases and recovery paths. E.g. 'If path not found, return a list of available files in that directory. If write fails due to permissions, suggest using a different directory.'