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

Annotations already declare readOnlyHint=true and idempotentHint=true, so the safety profile is known. The description adds that it returns a direct link for same-day delivery, which is informative but not deeply behavioral. It does not mention auth, rate limits, or any side effects beyond what annotations imply, so it adds only moderate context.

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 compact and front-loaded, stating the core function in the first sentence. The bulleted trigger list is concise and organized, adding practical usage examples without unnecessary fluff. 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?

Given the simple tool (2 params, full schema coverage, good annotations), the description sufficiently covers what the tool does and its trigger conditions. It states the return type (direct link) and the delivery context. It could mention response structure, but that is not necessary given the simplicity and annotation coverage.

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 100%, and both parameters (recipeSlug and postalCode) are already well-documented with examples in the schema. The description does not add any additional parameter semantics beyond restating that it deals with recipe ingredients and delivery, so the baseline score of 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?

The description uses a specific verb ('Get') and resource ('Instacart delivery information for recipe ingredients'), clearly stating it returns a direct link to order groceries. It distinguishes itself from sibling tools like shopping_generate_grocery_list by focusing on Instacart-specific delivery. The trigger examples further reinforce the purpose.

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 trigger list explicitly gives example phrases for when to use the tool, such as 'order ingredients for X' and 'Instacart delivery for X'. This provides clear context. However, it does not explicitly mention alternatives or when-not-to-use cases, 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.