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

Annotations already establish readOnly/idempotent/non-destructive, so the bar is low, yet the description adds real behavioral context beyond them: default exclusion of unverified gates, the mint-vs-secondary-trade gate distinction, and a scoping disclaimer that the result says nothing about who may legally buy. It does not discuss pagination or result shape, but those are covered by schema and output schema.

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?

Four dense sentences, front-loaded with the defining property before the mint/trade nuance and the legal disclaimer. Each sentence carries information — the gate distinction, the strictness rule, and the scope limitation — with no filler, though the prose is heavier than a typical filter tool warrants.

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 full schema coverage, an output schema, and rich annotations, the description only needed to convey what the filter means and where its boundaries lie — and it does so thoroughly, including the strictness default and the legal caveat. Nothing needed to invoke 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 description coverage is 100%, so the baseline is 3. The prose clarifies the concept behind include_unverified and the gate semantics, but adds no parameter syntax, formats, or defaults beyond what the schema already documents (limit, offset, pillar enum, min_yield_pct).

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 pins down a precise resource set — instruments whose secondary-market gate requires no KYC and that a self-custody wallet holds — and distinguishes that property from mint-level permissioning. It never states the operation in verb form ('find/list/return'), leaving the agent to infer that a collection is returned, but the defining criteria are unusually specific and separate it from siblings like find_tokenized_security.

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?

Strong context on inclusion semantics: 'Strict by design — an instrument whose gate is merely unverified is excluded,' and the explicit rule that include_unverified is only for 'what MIGHT be open, never to answer what IS open.' It does not route the agent among siblings (find_tokenized_security, search_yield_products) or state prerequisites, so it stops short of explicit when/when-not against alternatives.

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