reddit_get_user

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

With readOnlyHint=true already in annotations, the description adds meaningful behavioral context: no login needed, works for any public account, and suspended/shadowbanned accounts return 404 instead of an empty profile. This error-handling disclosure goes well beyond what annotations convey and helps the agent interpret results correctly.

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 sentences with zero filler. The first sentence states the core function, and the second handles auth and edge-case behavior. Every clause earns its place and the most important information is front-loaded.

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 one-parameter read-only tool, this description is nearly complete: it names the output fields (karma, age, flags), clarifies auth requirements, and covers error behavior. The only slight gap is that 'flags' is loosely defined and the exact response shape is not described, but no output schema is provided and the description still gives enough for an agent to know what to expect.

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?

Input schema coverage is 100%, including a description explaining 'Reddit username without the `u/` prefix, e.g. "spez".' The tool description does not add further parameter-specific detail, but the schema already fully defines the only parameter. Baseline 3 is appropriate because the description neither detracts from nor enhances the schema's high 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?

The description starts with a specific verb and resource: 'Get a Reddit account's karma, age and flags.' It clearly identifies the account-level scope, which distinguishes it from sibling tools like reddit_get_post, reddit_get_subreddit, reddit_list_user_posts, and reddit_list_user_comments. The mention of 'account' makes the purpose unambiguous.

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 states a clear usage condition: 'Works for any public account without a login.' This tells the agent that no authentication is needed and the tool is broadly applicable. It does not explicitly name alternatives or state when not to use this tool, but the context is clear enough for selection among siblings.

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