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

No annotations are present, so the description carries the full behavioral burden. It truthfully describes a read-only listing operation and the data included, but does not comment on authentication, pagination, or the exact shape of the returned link. For a simple list call this is acceptable, though more operational context would improve it.

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?

One clear sentence that front-loads the action and lists the returned payload. No 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?

For a zero-parameter list operation, the description covers what is returned (instruments, session, link) and distinguishes it from sibling tools. It lacks an explicit statement of output formatting, but the tool is simple enough that the description suffices.

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 tool takes zero parameters, and the schema already reflects this (100% coverage). With no parameters, the description has nothing to add; baseline of 4 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 the exact verb 'List', the resource 'instruments SPECTRE Markets publishes a levels board for', and the output fields (session, link). This clearly distinguishes it from sibling tools like get_levels and get_paths, which are presumably narrower data fetchers.

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 implies its use for discovering available instruments, but it does not explicitly mention when to prefer this over siblings or when not to use it. No exclusions or alternatives are named.

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