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

Annotations already cover the read-only, non-open-world profile, so the description's added value is the content shape it exposes: system prompt, template, example, tips, FAQ. That tells the agent the response is a complete document rather than metadata, which is genuinely useful. It doesn't mention size, truncation, or error behavior for unknown slugs.

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?

Two short sentences with the primary action front-loaded and the prerequisite second. No filler, no repetition of the title.

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 carries the burden of explaining what comes back, and it does so by enumerating the returned sections. Combined with annotations covering safety and the schema covering the single parameter, an agent has everything needed 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 slug property already carries an example, so the schema does the heavy lifting. The description adds only provenance ('slugs come from list_packs'), which is helpful but minimal — baseline 3 applies.

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 a specific verb and resource: 'Return the full raw Markdown ... of a free pack by slug.' The 'free pack' qualifier implicitly separates it from get_buy_link and get_pack-style siblings, though it never names the contrast explicitly.

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?

'Slugs come from list_packs' gives the agent a concrete prerequisite workflow for obtaining the required argument, which is the main usage risk here. It stops short of stating when-not to use it, but the free-only scope is implied by the name and description.

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