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

Goes well past the annotations: real-time rather than cached, a per-call credit cost, a documented return shape (always a JSON file link plus inline payload, truncated when large, in the API's own ordering), and the warning that body structure varies by marketplace. The axs plan prerequisite is exactly the kind of auth/permission context annotations cannot express.

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 the purpose and scope, then layered caveats, so an agent gets the essentials in the first clause. It is dense and runs long with several marketplace-specific asides, but each sentence carries non-redundant information rather than filler.

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?

With no output schema, the description fully compensates by explaining the dual return form (file link plus inline), truncation behavior, ordering, and per-marketplace body variation. Combined with the credit cost and plan requirement, an agent has everything needed to call it and interpret the result.

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%, including the platform-specific 'mode' values and the bare-event-ID allowance, so the schema carries the parameter burden and a 3 is the baseline. The description adds no syntax or format detail for platform, event_url, or mode beyond what the schema already states.

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?

Opens with a specific verb and resource plus a hard scope constraint: live ticket listings for ONE event on ONE marketplace. The 'ONE event on ONE marketplace' phrasing implicitly distinguishes it from the multi-marketplace sibling compare_marketplaces, and the enumerated fields (section, row, quantity, price, fees) make the output target concrete.

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 real decision context: 1 API credit per call, axs requires a Pro plan or above, and primary platforms (ticketmaster, dice, eventbrite, axs) return face-value offers rather than resale listings. What it lacks is explicit routing against the siblings (analyze_listings, compare_marketplaces, find_events) — it never says when to prefer one of those instead, 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.