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

Annotations already declare readOnlyHint=true and idempotentHint=true, so the agent knows it's a safe, side-effect-free operation. The description adds valuable context: it returns the cheapest live offer and compatibility as declared by the selling store, which indicates the source of data and potential variability. It does not over-explain destructive behavior since none exists.

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, front-loaded with the primary purpose, and each component (search scope, return content) earns its place. It's concise but not overly terse—it gives enough detail without redundancy. Minor deduction for not being perfectly optimized, but it's well-structured.

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 tool's complexity (7 optional filters, output schema exists), the description is complete enough for an agent to understand its functionality and invoke it correctly. The output schema likely describes the return structure, so the description need not repeat it. It covers the core value proposition and key constraints like store cross-reference.

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 high (86%), so most parameters are already described in the schema. The description adds extra context by explaining the return is the 'cheapest live offer' and mentions 'discount' which helps interpret 'on_sale' and 'max_price_eur'. It also references list_stores for the store parameter, going beyond the schema. This added value lifts it above baseline.

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 searches the fsaircraft.net catalog of payware MSFS add-ons across all tracked stores, and specifies what it returns (cheapest live offer, discount, compatibility). This verb+resource+scope is precise and distinguishes it from generic sibling tools like 'search' and 'list_addons_for_aircraft'.

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 when to use it: when searching for add-ons by free text with cross-store filtering, and mentions the 'store' parameter references list_stores for slugs. However, it doesn't explicitly contrast with siblings like 'search' (which might be broader) or 'compare_prices' (which might be for price comparison). Still, the context is clear for most use cases.

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