reddit_user_profile

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

Annotations already indicate readOnlyHint=true and destructiveHint=false, so the safety profile is covered. The description adds value by detailing the return contents (username, id, karma, account age, flags, avatar) and providing an example, which goes beyond the annotations.

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 two sentences plus an example, front-loaded with the verb and resource, and contains no filler. Every sentence earns its place.

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?

For a simple, read-only tool with one parameter and no output schema, the description provides a complete picture: what it does, what it returns, and an example. It appropriately scopes itself against numerous sibling tools, making it self-contained.

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?

The input schema provides 100% coverage with a clear description of the 'name' parameter including the 'u/' prefix constraint and path parameter status. The description only adds a redundant example ('spez'), so it does not significantly enhance parameter understanding beyond the schema.

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 a specific verb and resource: 'Fetch a Reddit user's public profile by username.' It distinguishes itself from sibling tools by focusing on profile metadata (karma, account age, flags) rather than posts or comments, and provides an explicit use case: 'vet or summarize a redditor.'

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 gives a clear use case ('Use to vet or summarize a redditor'), implying when this tool is appropriate. It does not explicitly name alternatives like reddit_user_comments or reddit_user_submitted, but the distinction between 'profile' and 'activity' is clear enough.

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