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

Annotations already declare readOnlyHint=false and destructiveHint=false. The description adds one useful behavioral detail beyond structured fields: 'Counts no site allowance,' i.e. it does not consume quota. It says nothing about auth requirements, rate limits, or return format, so added value is modest but real.

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 short sentences with no filler, and the core purpose is front-loaded ahead of the usage hint. Tight and easy to scan, though the closing quota note is slightly abrupt.

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, no-required-parameter listing tool with a fully documented schema and no output schema, the description covers what the tool does, why to use it, and its quota behavior. Return ordering is handled by the limit parameter's schema description.

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%: to/from dates and the limit range are fully documented in the schema. The description adds no parameter syntax or format details beyond that. Baseline 3 applies when the schema does the heavy lifting.

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: 'The catalogue of technologies we track, with how many sites use each.' It clearly conveys the scope (technologies plus usage counts) and its role as a name reference. It does not explicitly name or contrast with siblings like technology_sites or stack_breakdown, so differentiation is implied rather than stated.

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 a clear use case: 'Use this to find the exact technology name to pass to the other tools.' This tells the agent when to reach for it (resolving technology names for downstream calls). No explicit when-not condition or named alternative is given, so it stops short of full routing guidance.

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