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

With no annotations, the description carries the full burden of behavioral disclosure. It explains that the tool computes net EV after exit costs, presents a verdict, and includes a disclaimer ('NFA'). It does not detail data freshness or rate limits, but the core analytical behavior is transparent and safe.

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 long and front-loads the primary purpose, then follows with methodology and return-value information. Every clause adds value, and there is no filler or redundancy.

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 lack of an output schema, the description adequately explains the return verdict ('POSITIVE_EV / HOUSE_EDGE / NEGATIVE_EV') and the main evaluation dimensions. It leaves machine-code specifics to the schema, but the overall concept is sufficiently clear for an agent to select and invoke the tool correctly.

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?

The schema covers all four parameters (100% coverage), but the description adds meaningful semantics by explaining the buyback floor (85-93% of insured value, ≤72h) and marketplace fee (2% + fill-risk). This enriches the meaning of the exit_strategy parameter and clarifies the 'net edge' concept, going beyond the schema definitions.

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 opens with a specific verb ('Scan') and resource ('Jupiter Gacha (Collector Crypt) tokenized-card packs'), clearly stating the tool's purpose. It explicitly defines the computation (net-of-exit expected value) and the verdict types, making it easy to distinguish from sibling tools that focus on generic tokens or wallets.

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 provides clear context for when to use this tool: to evaluate the realizable EV of Gacha packs, with a comparison of exit strategies. It does not explicitly name alternative tools or exclusion criteria, but the sibling list contains no overlapping Gacha/EV scanner, so the context is sufficient.

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