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

No annotations are provided, so the description carries the full burden. It hints at read-only listing and says the return includes on-chain ids, but it says nothing about whether unfiltered calls return all instruments, ordering, result size, or pagination — significant gaps for a list endpoint with zero annotation coverage.

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?

Two compact sentences with the resource and return value front-loaded and the format detail second. Nothing is wasted, though the fragment style borders on terse under-specification.

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 annotations, no output schema, and 0% schema coverage, the description should do more: it omits the 'underlying' filter, default behavior when no filters are given, and any sense of return size or ordering.

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 0%, so the description must compensate. It does usefully specify the accepted expiry formats ('YYYYMMDD or unix seconds'), which the schema does not, but it never mentions the 'underlying' parameter at all, leaving one of two parameters undocumented.

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 names the resource ('Instruments') and what is returned ('their on-chain ids'), and the parenthetical '(expiry x strike x call/put)' explains the instrument's identifying structure, which makes the object concrete. It doesn't differentiate from sibling list_markets, so it stops short of a 5.

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?

There is no explicit statement of when to call this versus list_markets or the quote tools, and no mention of whether filters are optional. Usage is only implied by the name and the mention of an expiry field.

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