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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint, so the safety profile is covered. The description adds genuine value by revealing the grouping of results (accepted vs pending_in vs pending_out), which is behavioral/return context not in any annotation — but it is cut off mid-thought and says nothing about ordering, counts, or whether blocked contacts appear.

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?

Very short and front-loaded with the key fact ('Your contacts'), but the trailing 'and...' means the text is incomplete rather than concise — the enumeration was started and never finished, so space was spent without delivering the payload.

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 zero params, no output schema, and full annotation coverage, the bar is low and the agent can invoke this safely. However, since there is no output schema, the description is the only source of return-shape information, and it truncates exactly where that information would be delivered.

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 baseline is 4; the description correctly implies a no-argument listing. No parameter meaning is required or missing.

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?

Identifies the resource as the caller's own contacts and enumerates the relationship buckets returned (accepted, pending_in, pending_out), which separates it from contact_request/contact_accept/contact_block. The sentence is truncated at 'and...', so the full scope is not stated, keeping it below 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 when-to-use guidance and no named alternative — an agent is not told to prefer directory_search for finding strangers or contacts_mine only for its own network. Usage is only implied by the word 'Your'.

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