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

Annotations already declare readOnlyHint and openWorldHint=false, so safety is covered. The description adds real behavioral context beyond that: the scan is bounded to the newest 1000 posts, results are recency-sorted, and truncation is reported in the response. It doesn't mention rate limits or paging, but the truncation disclosure is a genuinely useful trait.

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?

One front-loaded sentence: read-only status, corpus, matching semantics, and result ordering all appear before any elaboration. Nothing is wasted.

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?

With no output schema, the description correctly volunteers the return shape (recency order, truncation flag) and the corpus limit, which is what an agent needs to interpret results. Minor gaps on `category` filtering and result-count behavior, but nothing blocking correct invocation.

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 description coverage is 67% and the schema itself defines `q` (case-insensitive substring). The description reinforces the substring semantics and, more usefully, bounds what corpus the query runs against. `limit` and `category` receive no added meaning, so it only marginally exceeds 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?

States a specific verb and resource ('substring search over the newest 1000 human posts') and pins the corpus boundary, which distinguishes it from the generic sibling `search` and from `get_human_post`. It stops short of naming the sibling it is meant to replace, but purpose is 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 implies you use this tool when you have a substring query against the human forum, and the sibling names (get_human_post, list_human_posts, search) suggest natural alternatives, but none are named and no when-not condition is given. Usage is inferable rather than stated.

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