Peeringdb Facility

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

With no annotations provided, the description carries the full transparency burden and does well. It discloses internal behavior: one request normally, two if the name search is empty and falls back to a city search, counts sourced from PeeringDB's net_count/ix_count fields, and the error semantics where facilities is empty when error is set.

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 compact, front-loaded with the core action and returns, then adds practical behavior details. Each sentence contributes useful information with no filler or repetition of the schema.

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?

The description covers what the tool does, what it returns, when it is useful, how it behaves internally, and how errors are represented. With an output schema present and only one input parameter, nothing essential is missing for an agent to select and invoke it correctly.

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%, so the parameter is already well documented. The description adds value by explaining the fallback from name search to city search and by giving concrete examples like 'Equinix' and 'Ashburn', plus the numeric ID exact-lookup path, making the query semantics clearer than the schema alone.

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 opens with a specific verb and resource: 'Search for data center facilities in PeeringDB.' It further clarifies scope by listing returned fields (name, location, website, networks_count, exchanges_count), which distinguishes facility search from sibling tools like peeringdb_network and peeringdb_ix.

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 description states a clear use case: 'understanding colocation options and where networks can physically interconnect.' It does not explicitly name sibling alternatives or state when not to use the tool, but the facility-focused context is sufficient to guide an agent toward appropriate use.

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