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

Annotations already declare readOnly, idempotent, non-destructive, closed-world behavior. The description adds real value beyond that: it discloses the data source (MatterCatalog's published ledger read), that a ledger-read date is returned (freshness/staleness signal), and that non-ledger products are included with a caveat about bridged or claim-only listings. It omits any rate-limit or coverage-lag details, keeping it short of 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?

The purpose is front-loaded in a clean first sentence, but the second sentence repeats input forms already listed in the schema, and the third is a long run-on cataloguing every returned field. It is informative but dense and over-stuffed rather than tightly structured.

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 carries the full burden of describing return values, and it does so thoroughly: certificate IDs, dates, software/Matter versions, device type, network transport, ledger-read date, and MatterCatalog page links plus the page's own certification answer. An agent can decide whether the response meets its needs without calling the tool first.

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%, with both `query` (with example values) and `limit` (1-10 range) fully documented in the schema. The description restates the accepted query forms (name, brand, model, part number, CSA certificate ID) but adds no syntax or matching-behavior detail beyond that. Baseline 3 is appropriate when the schema carries the semantics.

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 ('checks whether a product holds a Matter certificate') plus the authoritative source (CSA Distributed Compliance Ledger via MatterCatalog's read). This is clearly distinguishable from sibling lookup tools like where_to_buy or compare, which the description implicitly excludes with 'No prices.'

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 a clear context of use: look up certification status by product name, brand, model, part number, or CSA certificate ID, and notes it also surfaces non-ledger (bridged/claim-only) products. It does not explicitly name an alternative tool or state when-not to use it, so the agent must infer the boundary against find_matter_devices.

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