ck_fs_grep

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

The description adds significant context beyond annotations: it declares read-only behavior ('Read-only — no files are modified'), explains the fixed-string default with option to switch to regex, describes output format (matching lines with file path and line numbers), and notes the default limit (50). Annotations already indicate readOnlyHint and idempotentHint, and the description aligns perfectly without contradiction.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is concise with five sentences, each carrying essential information. It front-loads purpose, then covers behavior, parameter hints, output, and sibling differentiation. No redundant or extraneous text.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the parameter count of 7, high schema coverage, and presence of an output schema, the description covers all key aspects: purpose, read-only safety, search modes, scope, result limits, output format, and alternatives. It is self-contained and leaves no critical gaps for agent decision-making.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is high (86%), so baseline is 3. The description adds meaning beyond schema by explaining that query uses fixed-string search by default with the option fixed_strings: false for regex, that path can be a relative directory or glob, and that limit caps results with a default of 50. These clarifications help an agent select correct parameter values.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the tool's purpose: 'Search file contents using grep-style pattern matching' with a specific verb and resource. It explicitly distinguishes from siblings by naming ck_fs_find and ck_fs_read for alternative tasks.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides explicit when-to-use guidance: 'Use ck_fs_grep to find code patterns or strings inside files.' It also tells when not to use it by referencing sibling tools for name-based search or file reading. It explains default behavior (fixed-string) and how to change to regex.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.