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

Annotations already declare readOnlyHint and openWorldHint, so the safety profile is covered. The description adds genuinely useful behavioral detail beyond that: results come in Baidu's own ranking order and are capped at 10 suggestions. This is more than the annotations provide, though return shape specifics are left to the output schema.

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 tight sentences with no filler; the core function is front-loaded and the usage hint follows. Every clause 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 two-parameter suggest tool with annotations covering safety and an output schema covering return values, the description supplies everything needed to call it correctly: purpose, language scope, ordering, and result cap.

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 100%, so both parameters are already documented in the schema. The description restates the prefix input and the 10-suggestion cap but adds no syntax or format detail beyond what the schema already supplies, matching the baseline 3.

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 ('Returns Baidu search-box autocomplete completions') scoped to a query prefix, and distinguishes itself from the sibling baidu_search by clarifying it is autocomplete, not full search. An agent can identify the tool's function without opening the schema.

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?

Gives clear usage context ('Use for Chinese-language keyword ideas'), which tells the agent when this tool is appropriate and implicitly scopes it to Chinese-language prefixes. It stops short of naming alternatives or exclusions (e.g., other suggest tools), so it is not a full when/when-not routing statement.

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