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

The description goes beyond the annotations by disclosing critical behavior: it has a fallback chain that ends in community-sourced knowledge, claims to always return results, and specifies rate limits (10 calls/day) and no API key. This is far more than the readOnly and openWorld hints alone, giving the agent a clear picture of reliability and constraints.

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 a compact paragraph of four sentences, each providing distinct value: source chain, fallback behavior, usage domains, and return format/rate limits. No redundant phrases, and all information is front-loaded with the fallback chain first. It's an model of efficient, information-dense writing.

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 one-parameter tool, this description is exceptionally complete. It includes the return structure, source values, fallback behavior, rate limits, and appropriate use cases. The annotations cover safety (read-only) and open-world nature. There is no significant missing information an agent would need to invoke and interpret results correctly.

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?

The schema covers 100% of the parameter (query) with a description and examples, so the baseline is 3. The description itself does not add further parameter-specific semantics beyond what's in the schema; it repeats the concept of a search query but without extra detail. The schema already carries the burden effectively.

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 the tool performs a 'web search' with a specific fallback chain across multiple sources, and even lists the exact sources. It distinguishes itself from siblings by emphasizing its multi-source nature and automatic fallback, which is not present in other tool names. The 'Best for' section further clarifies its scope.

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 specific use cases ('tech/AI/crypto queries, current events, documentation discovery') which is clear context. However, it does not explicitly mention alternatives or when not to use this tool, such as pointing to x711_deep_search for more in-depth queries. Still, the 'Best for' phrasing effectively guides appropriate use.

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