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

Annotations already indicate readOnlyHint, idempotentHint, and destructiveHint=false, covering safety. The description adds important behavior: it returns ready-made strings with quantities (not just recommendations), and it details a specific counting rule for flanged fittings. This adds value beyond the annotations, though it doesn't mention any side effects (none expected given annotations).

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?

The description is two sentences with no fluff. It front-loads the purpose, then adds a crucial counting rule that affects output. Every sentence 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 read-only, idempotent tool with one well-documented parameter and no output schema, the description provides enough context: what it does, how to use the output, and a special rule. It lacks examples of output format, but given the simplicity and annotations, it's sufficiently 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 100%, so the single parameter 'cart_id' is well-documented. The description references cart_id indirectly by mentioning 'позициям корзины' and 'build_cart', but it doesn't add new information about the parameter beyond the schema. Thus, a baseline of 3 is appropriate.

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 tool's function: suggesting add-on items for cart positions, with a specific verb 'suggest' and resource 'accessories_for_cart'. It distinguishes itself from siblings like 'get_recommendations' and 'select_actuator' by focusing on cart-specific accessories and providing ready-to-use strings for 'build_cart'.

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 implies usage: it should be used when the user has a cart built via 'build_cart', and the output can be directly fed back into 'build_cart'. It also gives a specific rule for flanged fittings, which acts as a usage guideline. However, it does not explicitly say when NOT to use it or mention alternatives.

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