Get one published abatement contractor by its slug.
Replace each placeholder with a value matching the input schema. Only required parameters are included; add optional parameters as needed.
{
"id": 1,
"jsonrpc": "2.0",
"method": "tools/call",
"params": {
"arguments": {
"slug": "<slug>"
},
"name": "get_listing"
}
}| Name | Required | Description | Default |
|---|---|---|---|
| slug | Yes | The listing slug. |
Changes observed during successful MCP inspections.
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and a closed-world scope, so the safety profile is covered. The description adds one genuinely new behavioral fact: only 'published' contractors are returned, implying unpublished slugs yield nothing. It does not say what happens on an unknown slug (error vs empty result), which is the remaining behavioral gap.
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?
One short sentence with zero filler, and the most important qualifier ('published', single record, slug lookup) is front-loaded. Nothing to trim and nothing padded.
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 trivial single-parameter read tool with full annotations, the description is nearly sufficient. However, with no output schema, the agent gets no signal about the returned shape or about not-found behavior, which is the main thing an agent would still need to guess.
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% and the single slug parameter already documents its pattern and length constraints. The description adds nothing beyond 'by its slug', so baseline 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 gives a specific verb ('Get'), a specific resource ('one published abatement contractor'), and the lookup key ('by its slug'). 'One' implicitly contrasts with the sibling search_listings, but no sibling is named explicitly, so it stops short of a 5.
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?
Usage is implied clearly enough: use this for a direct slug-based lookup of a single contractor. The word 'published' hints that unpublished records are out of scope, but there is no explicit when-not guidance or named alternative (e.g. search_listings for discovery).
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
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