upload_file

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

Discloses key behavioral traits: file type rejection with 422 error, append-only nature (files cannot be deleted or modified). This adds context beyond annotations (destructiveHint: true) by explaining the specific mutability constraints.

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?

Concise, well-structured, and front-loaded with the core purpose and constraints. Every sentence adds value without redundancy.

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?

Covers most aspects: purpose, accepted types, outcome, limitations. However, lacks detailed description of return value structure (e.g., exactly which fields in compact vs full response). Minor gap given no output schema.

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 100%, but description adds value by explaining the purpose of verbose (saves ~90% context) and fileName override. This goes beyond schema descriptions, meriting a 4.

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 the action (upload a local file), accepted file types, and expected outcome (get file ID). Distinguishes from sibling attach_file by noting that this tool is for uploading while attach_file links to a record.

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 specifies when to use (upload files) and what file types are accepted/rejected. Provides behavioral guidance: files are append-only and cannot be modified or deleted via API. Points to attach_file for subsequent linking.

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