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

With no annotations, the description carries the full burden; it does disclose that only 'covered' exchanges are returned and names the fields in the payload, which is useful. It stops short of saying whether the result is a full static reference set, whether coverage varies by data subscription, or anything about ordering or pagination.

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?

A single front-loaded sentence with no filler. The identifying detail (MIC standard, returned fields) arrives immediately.

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-argument reference-list tool with no output schema, the description covers the resource, the identifier standard, and the notable returned attributes. Only the scope of 'covered' and result size remain unspecified, which is a minor gap at this complexity.

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, so there is nothing for the description to disambiguate; baseline of 4 applies. The mention of ISO 10383 MIC gives context for the returned identifiers rather than adding parameter meaning.

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 states a specific verb and resource ('List covered exchanges') and pins down the identifier standard (ISO 10383 MIC) plus the attributes returned (country, city, timezone). That is enough to distinguish it from siblings like list_financial_centres or list_calendars, though it never explicitly contrasts itself with them.

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 statement of when to use this versus the many sibling reference-list tools (list_currencies, list_calendars, list_financial_centres), nor any prerequisites or exclusions. Use is only implied by the phrase 'covered exchanges'.

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