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

Annotations already declare readOnly, idempotent, openWorld and non-destructive, so safety is covered; the description adds the credit cost ('Cost: 1 credits') and the ordering of returned apps, both behavioral facts not present in structured fields. No mention of failure modes for unknown developers, so it stops short of 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 payload description comes first, followed by the id-syntax hint and the cost — reasonable front-loading with no filler. The parenthetical '(most-rated first)' and the terse 'Cost: 1 credits' fragment keep it tight.

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 usefully enumerates the returned fields and the cross-store inclusion, which is what an agent needs to decide whether to call it. Minor gaps remain around error behavior and whether the cross-store match can be absent.

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 the dev format, store disambiguation and format enum all documented in the schema, so the baseline of 3 applies. The description echoes the 'dev <store>:<id>' convention and nothing more.

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 precisely what the tool returns: a developer's profile fields (name, website, country, app count, ratings, installs), their apps sorted most-rated first, plus the same company in the other store. That return contract is specific enough to separate it from siblings like get_app or search_apps.

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?

Implies the entry path by noting 'get_app shows the developer id as dev <store>:<id>', which tells the agent how to obtain the required dev value. But it never states when to prefer this over get_competitors or search_apps, nor any exclusions.

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