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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, so the safety profile is covered elsewhere. The description earns credit for disclosing a non-obvious behavioral rule: on a connection approved for chosen sites, only those sites are returned, while a full-account connection returns everything the seat can see. That nuance materially changes how an agent interprets an empty or short result; it stops short of covering ordering or result-size behavior.

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 sentence front-loads the core action and returned fields, then appends the account-wide versus chosen-sites qualification. Nothing is redundant with the title or annotations, and no sentence could be dropped without losing information.

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 read tool with no output schema, the description supplies the essentials: what is listed, what fields come back, and how connection type affects scope. It leaves only minor gaps, such as result ordering or expected cardinality, which are unlikely to block a correct call.

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 the schema carries no semantics an agent needs help interpreting and the baseline is high. The description correctly adds no parameter discussion, wasting no space on arguments that don't exist.

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 gives a specific verb and resource ("List the sites this connection can use") and states what each entry contains (ids and domains), so an agent can immediately tell this is a scoped site enumeration. It doesn't explicitly contrast itself with siblings like get_capabilities or select_site, but no other sibling appears to be a site lister, so the ambiguity is low.

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?

Usage is implied rather than stated: the description frames the result in terms of what 'this connection can use', which hints this is a discovery step before operations like select_site. However, it never says when to call this versus a sibling, nor does it state any preconditions or exclusions outright.

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