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

With no annotations provided, the description carries the burden. It discloses that results are cited to manufacturer documentation with source URLs, covers only the 409-model directory, and clarifies input requirements (slug or brand+model). It does not mention error handling or read-only nature, but the core behavior is transparent.

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 concise (about 3 sentences) and front-loads the core function, then gives usage context and scope. It is efficiently worded without redundancy, though a bullet list could improve scannability.

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, the description adequately explains what the tool returns and its scope. It covers the 409-model limitation and the citation behavior. It could mention not-found handling or that it is read-only, but for a lookup tool this is sufficient for an agent to use 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 coverage is 100%, so baseline is 3. The description adds value by explaining that either slug OR brand+model can be passed, which is not evident from individual parameter descriptions. This clarifies the invocation pattern 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 clearly states the tool returns default gateway IP, admin username/password, credential type, and factory-reset steps for a router model, with citations. It distinguishes from siblings by specifying it is for default login info and not a listing or wildcard search, which sets it apart from potential search or compliance 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?

Explicitly states when to use: after lookup_mac identifies the vendor, or whenever a user asks for default login, factory password, gateway address, or reset procedure. It also excludes listing/wildcard search, guiding the agent away from misuse.

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