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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safety profile is known. The description adds that download metadata is included 'when available', which is a specific behavioral detail about response content. This is useful context beyond the annotations, though it doesn't describe error handling or pagination (not needed for a single fetch).

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?

A single, front-loaded sentence that states the action, target, and additional detail (download metadata) without fluff. Every word earns its place.

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 low-complexity read-only operation with one well-documented parameter and an output schema (not shown but indicated), the description fully covers what an agent needs to call it correctly. It even adds the download metadata caveat, and the safety profile is already in annotations.

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% – the slug parameter is described as 'Free resource slug.' The description doesn't add any additional meaning about the parameter beyond what the schema provides. Per the baseline for high schema coverage, this is a 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 states a specific verb ('Fetch') and resource ('one free resource') with an identifier ('by slug'). It clearly distinguishes from list_resources (which lists) and other get_* tools that target different resource types (e.g., get_kit, get_benchmark). The word 'one' clarifies it's a single-item operation.

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 clear context: use this to get a single free resource by slug. While it doesn't explicitly name alternatives or exclusions, the context ('one' and 'free resource') implies it is for individual fetches rather than listing or other resource types. This is sufficient for an agent to route correctly.

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