get_app_details

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

Annotations already declare readOnlyHint=true, openWorldHint=true, idempotentHint=true, and destructiveHint=false, covering the safety profile. The description adds value beyond annotations by stating 'No API key required', which is a key operational detail not in annotations or schema. It also lists what data is returned (review recommendation count, Metacritic score), giving a fuller picture of the tool's output. Since annotations cover most of the behavioral profile, the extra detail justifies a 4 in the context of full coverage.

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 description is two sentences: the first states the resource and return fields, the second covers prerequisites and authentication. It is front-loaded with the core purpose and field list, then addresses usage guidance. Every sentence earns its place; there's no fluff or redundancy.

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?

Given the tool has only 1 parameter, full schema coverage, and a rich annotation set (read-only, idempotent), the description is sufficient for correct invocation. It covers what it returns, prerequisites (appid discovery), and authentication needs. The technical note 'No API key required' is a critical completeness piece for a tool that often requires keys in similar APIs. Nothing essential is missing for an agent to call it 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% and the parameter (appid) already has a clear description with examples. The description doesn't need to add much, but the tool description does mention the first step of the workflow ('Use search_store first') which is relevant to the parameter's usage (finding the appid). The schema's description of appid is thorough, so the definition adds marginal value beyond it, but the baseline is high due to coverage, making a 4 appropriate.

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 clearly states what the tool does: 'Get full store details for a game/app by appid.' It enumerates the returned fields (type, description, developers/publishers, price, etc.), which distinguishes it from siblings like search_store (which finds appids) or get_global_achievement_percentages (which gets achievements). This is specific and immediately actionable.

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?

The description gives explicit guidance: 'Use search_store first if you only have a name.' This directly tells the agent when to use this tool vs. its sibling, which is strong. The input schema also reiterates this with 'Use search_store to find an appid from a game name.' However, it doesn't detail alternative scenarios or non-usage cases, so a 4 is appropriate rather than 5.

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