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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safety profile is covered. The description adds valuable behavioral context: '1 credit per tweet or profile' discloses the cost model, and 'Top may answer 403 (free)' warns about a possible error condition. This goes beyond the annotations and helps the agent anticipate outcomes.

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 three short sentences with no fluff. It front-loads the core purpose ('X advanced search') and then adds essential facts (operators, cost, availability) in a tight sequence. 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 search tool with no output schema, the description covers the key aspects: query format, cost, and product-specific behavior. It does not detail return structure or pagination, but the cursor parameter is documented in the schema. The tool is simple enough that this description is largely complete, though it could mention that People returns profiles, which is already in the 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 description coverage is 80%, so most parameters are documented in the schema. The description adds a note about the product parameter's availability (Latest vs Top 403), which is useful, but it doesn't significantly enhance understanding of q, count, fresh, or cursor beyond what the schema already provides. With high schema coverage, a baseline of 3 is appropriate.

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 'X advanced search' with a specific verb and resource. It distinguishes itself from sibling getter tools (like get_tweet, get_tweets) by emphasizing the query-based search with x.com operators, which is unique among the siblings. The tool's 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 provides some usage context by noting product availability ('Latest is always available; Top may answer 403'), but it does not explicitly state when to prefer this search tool over direct fetch siblings like get_tweets or get_user_tweets. The usage is implied rather than explicit, so a clear gap remains in guiding the agent to choose this over alternatives.

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