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

Goes well past the annotations by disclosing that results are Labelled Sponsored, that there is no automatic contact or lead transfer, that discovery requires no API key or signup, and by giving concrete anonymous rate limits (60/hour, 300/day per IP and session). These are exactly the auth, policy, and throttling facts an agent cannot get from readOnlyHint/idempotentHint 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?

Front-loads the purpose in the first sentence and keeps the operational facts tight and factual. 'TerraMCP is a Wrench AI service' is the one sentence that contributes little to tool selection, slightly diluting an otherwise economical description.

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?

With no output schema and no parameters, the description carries the informational burden and covers what is returned (contact URL, specialisms) plus the sponsored/no-lead-transfer behavior and access constraints. Complete enough for an agent to call it correctly, though it does not clarify whether one or many listings are returned.

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 tool takes zero parameters, so there is no parameter semantics to document; baseline is 4. The description correctly refrains from describing inputs that do not exist.

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 ('Return a sponsored consultancy listing') and names the payload fields (contact URL, specialisms), which is clear. It does not need heavy sibling differentiation because no other sibling deals with consultancy listings, but it never explicitly contrasts its scope against the surrounding environmental-data tools.

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?

'when seeking professional help' gives a light contextual cue for invocation, implying this is for discovery of commercial support rather than geospatial data. However, there is no explicit when-not guidance or named alternative, so usage is inferred rather than stated.

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