read_file

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

With no annotations, the description discloses read-only nature, no side effects/auth/rate limits, return fields including est_tokens for context budgeting, and error behavior ('Throws if the ID is unknown').

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?

Three focused sentences front-load purpose, then add return/error details and alternatives; no wasted words.

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?

Despite no output schema, it lists key return fields, error behavior, side-effect profile, and usage boundaries, which is sufficient for a single-parameter tool with rich sibling context.

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 covers the only parameter (id) at 100% with 'File ID'; description adds minimal semantic value beyond referencing 'by ID' and emphasizing a known file, meriting the baseline 3 for high schema coverage.

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?

Description states 'Read one file's full body and metadata by ID' with a specific verb and resource, and explicitly distinguishes from siblings via 'Use for a single known file' and alternative tool mentions.

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 states when to use ('single known file'), and provides clear alternatives for inspection (describe_file), batch (read_files), partial (read_file_lines/read_section), and path-based (read_file_by_path) scenarios.

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