read_file_by_path

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

Describes read-only, no side effects, auth, or rate limits. Details exact path matching, no symlink resolution, and error behavior (isError if not indexed).

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?

Four sentences with no waste. Information is front-loaded, well-structured, and every sentence adds value.

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?

No output schema, but description explains return shape and error case. All necessary behavioral details are covered.

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?

Single parameter fully described in schema. Description adds context that path must be absolute and exactly match indexed path, which enhances clarity.

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?

Clearly states it looks up a file by absolute path and returns same shape as read_file. Distinguishes from sibling read_file by specifying when to use each.

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?

Explicitly says use when agent has path but no ID, and to prefer read_file if ID is available. Also mentions trying refresh_index if not indexed.

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