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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is covered; the description adds value by disclosing the response shape (sections of list items, severity-grouped interactions, coupon price per dosage and quantity). It's a read operation, so no destructive/auth caveats are needed.

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?

One front-loaded sentence with the tool's function first, followed by the return breakdown and a source hint. Dense but every clause carries information; no filler.

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?

An output schema exists, so deep return-value documentation isn't required, yet the description still sketches the payload. Combined with the pointer to the companion tool for valid inputs, an agent has enough to call it correctly; only slug format is genuinely missing.

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 0%, so the description must carry the load. It names both parameters and implicitly reveals the valid topic values via the enumerated content types (side-effects, dosage, interactions), but never defines what 'slug' is or gives its format, so compensation is partial.

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+resource ('Get one GoodRx drug guide by slug and topic') and immediately enumerates the three content shapes (side-effects, dosage, interactions). It clearly distinguishes itself from the sibling goodrx_drug_guides, which supplies the input pairs.

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?

Explicitly routes the agent to goodrx_drug_guides for valid slug/topic pairs, which is the key prerequisite. It does not name close alternatives (e.g. goodrx_drug_info, goodrx_drug_prices) or state when this tool is the wrong choice, so it stops short of full when/when-not guidance.

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