MAC / OUI vendor lookup

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

With no annotations, the description carries the full burden and does substantial work: it discloses the longest-prefix-first resolution against IEEE registries, that sub-blocks (MA-M/MA-S/IAB) win over the MA-L registrar, and that randomized addresses return vendor: null plus cidRegistrant with a concrete example (DA:A1:19 = Google). It omits error behavior for malformed MACs and whether lookups are local or networked, so not a 5.

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-loaded with the core purpose before diving into resolution mechanics and return fields. It is dense with useful specifics, though the enumeration of returned fields runs long for a single-sentence-per-idea structure; every clause still earns its place.

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?

No output schema exists, so the description must describe returns, and it does so thoroughly: vendor, blockType, block start/end, OUI, kind, randomized flag, confidence, source registry file, plus the null-vendor/cidRegistrant special case. It lacks failure-mode coverage for invalid input, which is the main remaining 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?

There is a single parameter with 100% schema description coverage ('A MAC address in any format, e.g. F4:F5:E8:11:22:33'), so the schema already does the work and the baseline is 3. The description adds no additional input-side semantics such as accepted separators or validation rules.

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 ('Identify the organisation behind a MAC address') plus a second distinct capability (detecting randomized/private addresses), which no sibling covers. The sibling tools (get_router_defaults, check_router_compliance) are clearly different concerns, and the description makes that separation explicit.

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?

Gives concrete context for use (vendor identification, randomized-address detection) and explicitly routes a related need to a sibling: 'For the router's factory login, call get_router_defaults next.' It does not state exclusions or when this tool would be the wrong choice versus submit_correction, so it stops short of a full 5.

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