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

Annotations already cover safety (readOnly, idempotent, non-destructive, closed-world), so the description's job is to add context, which it does by listing what the response contains and adding the important caveat that finding no signs does not mean a message is safe. It doesn't discuss latency, rate limits, or handling of very long messages, but for a read-only analysis tool this is solid.

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 the first sentence, followed by parameter notes and then the return-value summary, so the agent can skim selectively. The sentence packing several scam-pattern examples is dense but informative rather than wasteful.

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 must explain the return value, and it does so precisely: signs found, Moda's explanation of each pattern, verification steps, and Moda's own rules. Combined with full purpose, parameter notes, and the safety caveat, nothing an agent needs in order to call and interpret this tool is missing.

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 schema already defines all three parameters and this sets the baseline at 3. The description restates each parameter with marginally richer detail, such as example context values (auction bid, want-to-buy post, listing), but adds no format or constraint guidance beyond what the schema provides.

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 specific verb and resource (checks a message for scam patterns) and scopes the inputs to message channels: Facebook message, text or email. It also lists concrete scam patterns it detects and cites the reference source (modacommunities.com/verify), which clearly distinguishes it from siblings like check_listing_words and check_moda_contact.

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?

It clearly defines the trigger situation (a message someone received about a deal) and gives scenarios such as a cold message after an auction bid, a buyer backing out, or a changed shipping address. It does not, however, explicitly name an alternative tool or state when not to use this one versus check_facebook_group_link or check_moda_contact.

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