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

Annotations already declare readOnlyHint=true and openWorldHint=false, so safety is covered. The description adds value beyond them by disclosing the returned fields (name, short description, live price, store link) and the default ordering when no query is supplied, which is exactly the kind of behavioral detail 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?

Three tight sentences, front-loaded with the action and resource, followed by what comes back and the no-query default. No filler, and every sentence carries information an agent would otherwise have to guess.

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?

For a simple two-parameter read-only search with no output schema, the description covers purpose, return shape, and default behavior, which is nearly everything needed. It stops short of explaining pagination beyond the first page or how price data is sourced, but those are minor for this complexity level.

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 both query and limit are already documented in the schema, establishing a baseline of 3. The description reinforces the empty-query semantics but adds nothing about the limit parameter or result truncation beyond what the schema states.

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: 'Search ElfHosted's catalogue of apps and bundles.' It also lists the return fields, so an agent knows this is a discovery/search tool rather than a comparison or setup tool. It does not explicitly contrast itself with compare_apps, which also operates on apps, so it falls short of a 5.

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 one concrete usage cue – omitting search words yields featured apps first, then the catalogue – which tells the agent how to browse rather than search. However, it never states when to prefer compare_apps or find_my_setup over this tool, leaving alternative selection to inference.

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