Ozon Product Card

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

Annotations already cover read-only, idempotent, non-destructive and open-world, and the description still adds substantive behavior: a Tier-1 curl_cffi attempt with a Tier-2 Chrome CDP fallback on 403, the hard prerequisite of running scripts/start_chrome_cdp.*, and two non-obvious data contracts (missing fields are None, never 0; an empty payload is healthy, not an error). That is exactly the context structured fields cannot convey.

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?

Front-loaded with purpose, then the fallback chain, then the data-contract caveats, then a pointer to the guide resource. The cross-platform script paths are a bit verbose for a description, but each sentence carries operational meaning.

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 one-parameter read tool with an output schema and full annotations, this covers what remains: failure modes (403), the prerequisite for the fallback path, interpretation of missing/empty data, and a guide:// resource for the full field list and error codes. Nothing an agent needs to call it correctly is missing.

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% and the single parameter's description already covers the accepted forms (SKU string, full URL, /product/<digits>/ path) and SSRF rejection. The tool description adds nothing about the parameter, so the baseline 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?

States a specific verb and resource: "Fetch Ozon product card data via composer-api.bx". An agent can tell it apart from ozon_search and ozon_reviews by the 'product card' framing, but the description never explicitly names those siblings as alternatives, so differentiation is inferred rather than stated.

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 guidance given is operational (tiered fetch, Cloudflare 403 fallback, Chrome CDP prerequisite) rather than selection guidance. There is no explicit statement of when to prefer this over ozon_search or ozon_reviews, so usage is implied by the tool name alone.

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