market_add

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

With no annotations, the description must disclose behavior. It reveals that missing required fields cause 422 errors and suggests recovery. However, it does not mention that this is a mutation (adds to cart) or any authentication/rate-limit details.

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 sentences, front-loaded with purpose, no extraneous text. Every phrase contributes guidance.

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 simple add-to-cart tool with no output schema, the description covers the key prerequisites and error handling. It could mention success indication but is generally 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?

Schema coverage is 80%; the description adds value by specifying the mapping from market_search output fields (especially 'store' from 'store_key'), which goes beyond the schema descriptions. It also implicitly covers the required parameters.

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 the action ('Add to cart') and the domain ('[Shop]'), with specific resource identification. It explicitly lists the four required fields from market_search, distinguishing it from siblings like market_cart_update and market_checkout.

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?

Provides explicit instructions to copy all four fields from market_search and warns about 422 errors for missing fields, advising to re-run market_search if needed. Lacks explicit when-not-to-use guidance but gives clear usage context.

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