Fetch a directory of ~700 Craigslist regional sites with area aliases, hostnames, coordinates, and timezones. Filter by country to identify the correct area for searches.
Directory of ~700 Craigslist regional sites with alias (the area value for searches), area code, hostname, country, region, coordinates, timezone and sub-areas. Flat 5 points per successful run.
| Name | Required | Description | Default |
|---|---|---|---|
| country | No | Country (optional). e.g. US |
Changes observed during successful MCP inspections.
v1.0.1Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations and no output schema, the description carries the burden, and it does disclose the returned field set plus the cost model ('Flat 5 points per successful run'), both useful. It omits side-effect/auth/pagination details, but for a static read-only directory lookup those are minor.
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 sentences: an opening field inventory and a pricing note. The resource is front-loaded and nothing is filler, though the long field enumeration is somewhat dense given there is no output schema to lean on.
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 1-optional-param reference tool with no output schema, the description supplies the field inventory that the schema cannot, making it callable without further context. Adding explicit guidance on how the alias ties into the search siblings would close the last 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 single optional 'country' parameter is fully documented in the schema (100% coverage, including an example), so the baseline is 3. The description mentions 'country' only as a returned field, not as a filtering input, adding no semantic value beyond the schema.
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 names a concrete resource (a directory of ~700 Craigslist regional sites) and enumerates the fields it contains, which clearly separates it from siblings like run_craigslist_categories and run_craigslist_postings. The phrasing is passive ('Directory of...') rather than an explicit verb, but the purpose is unambiguous.
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 only implied: calling the alias 'the area value for searches' hints that this tool is the lookup source for area parameters used by the posting/search siblings. There is no explicit when-to-use statement or named alternative, so the agent must infer the connection.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.