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

Annotations already cover safety (readOnlyHint=true, destructiveHint=false, openWorldHint=false), yet the description still adds real value: the shape of the comparison returned and, importantly, the partial-result edge case where products known only as alternatives come back under notListedOnPeerPush with name and website. That failure-mode disclosure is exactly what annotations cannot express.

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 purpose and usage, then return shape, then the edge case. Every sentence carries information, though the closing linking advice (websiteUrl vs peerpushUrl) is slightly tacked on and could be folded into the return description.

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 carry return semantics, and it does: shared/unique features, pricing differences, platform coverage, use cases, audiences, community metrics, plus the notListedOnPeerPush fallback. An agent has everything needed to call and interpret this tool.

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?

Only one parameter with 100% schema coverage, so the schema already documents the array, minItems=2, maxItems=5, and the example. The description restates '2-5 named software products' and adds that products are matched by name, which is marginal over 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?

Specific verb ('Compares') plus resource and cardinality ('2-5 named software products side by side'). This clearly separates it from siblings like peerpush_find_alternative and peerpush_product_details, which handle single-product or alternative lookups.

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?

States the triggering intent explicitly: comparison requests or 'which of several specific products to choose', with the example 'Vercel vs Netlify'. It implies rather than states the exclusion (use peerpush_find_alternative when you don't have named products), so it stops short of full when/when-not guidance.

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