Retrieve drugs listed in a GoodRx drug class by slug, including each drug's lowest displayed price and summary.
List drugs in a GoodRx drug class. Returns the drugs GoodRx lists for one drug class, with each drug's lowest displayed price and summary. Use a slug from /goodrx/classes.
| Name | Required | Description | Default |
|---|---|---|---|
| slug | Yes | Class slug from /goodrx/classes |
Changes observed during successful MCP inspections.
v1.17.9Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are provided, so the description carries the full burden. It discloses that results include each drug's lowest displayed price and summary, which is useful for a read-only listing, but says nothing about pagination, result limits, or ordering, leaving behavioral gaps for an unannotated tool.
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?
Three short, front-loaded sentences that each earn their place: purpose, return contents, then input acquisition. No filler, no repetition.
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 must convey return shape, and it does so briefly (drug list with lowest displayed price and summary), plus it names the source of the required slug. It omits pagination or count behavior, which keeps it from being fully complete.
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?
There is a single parameter with 100% schema description coverage, so the baseline is 3. The description's 'Use a slug from /goodrx/classes' merely restates the schema's own description of slug, adding no format or validation detail beyond it.
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: 'List drugs in a GoodRx drug class,' then specifies the scope ('one drug class') and the returned payload (lowest displayed price and summary). It does not explicitly name a sibling such as goodrx_classes or goodrx_drugs, so the agent must infer the boundary from context, keeping this just below a 5.
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?
'Use a slug from /goodrx/classes' tells the agent where the required input comes from, effectively routing it to the goodrx_classes sibling first. There is no explicit statement of when not to use this tool or how it differs from goodrx_drugs or goodrx_drug_options, so it falls short of a 5.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.