get_user_profile

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

With no annotations, the description carries the full burden. It usefully discloses that only public data is returned and enumerates the payload fields, but says nothing about auth requirements, error behavior for nonexistent or suspended accounts, or rate limits. It conveys read-only character implicitly through "public profile" rather than explicitly.

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?

Two short sentences, front-loaded with purpose and followed by scope. Every clause carries information; nothing is padded or redundant.

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 single-parameter read tool with no output schema, the field enumeration effectively stands in for a return-value description, which covers the biggest gap. The remaining shortfall is error and auth behavior, which is minor for a simple public lookup.

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% and the schema itself documents that the username excludes the u/ prefix. The description adds no parameter-level meaning beyond that, so the baseline of 3 is appropriate for a single fully-documented parameter.

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 gives a specific verb and resource ("Get a Reddit user's public profile") and enumerates the profile content (karma breakdown, bio, account age, avatar, trophies, gold status), which implicitly separates it from content-oriented siblings like get_user_posts and get_user_comments. It never explicitly names those siblings, so differentiation is inferential rather than stated.

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?

There is no when-to-use guidance, no mention of alternatives such as search_users when the username is unknown, and no exclusions. "Works for any public Reddit account" is a scope statement rather than usage direction, leaving the agent to infer routing entirely.

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