Build Google Flights Protobuf URL

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

The readOnlyHint annotation already indicates no side effects, and the description reinforces this with 'without making a network request.' It adds useful behavioral context by clarifying that the tool performs local construction only, which is meaningful beyond the annotation alone.

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 single, focused sentence with no filler. It front-loads the core action and resource, then adds the most important behavioral qualifier: no network request.

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?

Given the output schema exists and the input schema fully documents the request object, the description only needs to convey the tool's high-level purpose and side-effect profile. 'Build a real tfs protobuf search URL without making a network request' does exactly that, leaving no significant gap.

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 input schema has 100% description coverage, including a well-described nested request object with defaults, ranges, and field-level descriptions. The description itself adds no parameter-level meaning, so the 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 uses a specific verb ('Build') and resource ('tfs protobuf search URL') and adds the critical distinction that it does not make a network request. This clearly differentiates the tool from siblings such as discover_and_rank_complete and search_and_verify_top, which imply actual searching and verification.

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 'without making a network request' clause signals that this tool is for pure URL construction rather than executing a flight search, which gives an agent clear situational context. It does not explicitly name alternative tools, but the distinction from the sibling tools is strongly implied.

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