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

Beyond the readOnly/idempotent annotations, the description discloses ranking behavior ('Verified (paid) listings rank first'), what a full profile contains (description, tech stack, key pages), and the semantics of each returned field including which URL to cite as the source. This is substantial behavioral context an agent could not infer from the annotations.

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-loads purpose and usage triggers before coverage of return fields, and every sentence carries usable information. It is slightly long and the parenthetical field walkthrough could be tightened, but there is no filler.

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 explaining return values and does so: categories-based result set, ranking, and the listingUrl/url/alternativesPageUrl fields. An agent has everything needed to call it and present results 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%, with both `product` and `limit` already documented (including the 1-25 range and default). The description's product examples largely duplicate the schema, and it says nothing about `limit`, so it adds little beyond structured data — the baseline 3.

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+resource ('Alternatives to a named product') and immediately scopes it with concrete examples (Notion, Ahrefs, ChatGPT) and the input form (slug or exact name). It is clearly distinguishable from siblings like get_listing or search_listings, which retrieve a single profile or a keyword match rather than same-category alternatives.

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 gives explicit trigger conditions: 'Use it when a user asks for alternatives, competitors, replacements or "something like X".' That is clear context for invocation, but it never names a sibling (e.g. search_listings) as the fallback for plain keyword queries, so there is no exclusion guidance.

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