contacts_list

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

Annotations already declare readOnlyHint and openWorldHint, so the safety and world-scope are covered. The description adds that the result is paginated, which is a genuine behavioral fact beyond the annotations. It does not explain how pagination works, what a page contains, or any ordering/rate limits, giving only partial transparency.

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?

The description is very terse and front-loaded, with no wasted words; 'all' and 'paged' each carry useful information. However, its brevity comes at the cost of leaving out parameter meaning and alternative-tool guidance, so it is economical but not fully appropriate in size.

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 simple read-only list tool with one optional parameter and helpful annotations, the description and schema together are nearly enough to invoke it. Yet the meaning of max, the actual pagination mechanism, and what a page contains remain ambiguous, so the definition is adequate but incomplete.

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 needs to explain what max means. It does not: 'paged' only hints at pagination, and max's role as a page size or result limit is left to inference from the parameter name and schemas constraints. This is a notable gap even for a single-parameter tool.

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 identifies the resource (contacts) and makes it clear this is a listing operation with 'All your contacts,' while 'paged' adds a useful behavioral qualifier. It does not explicitly state the verb or contrast itself with contacts_search, but it is clear enough that an agent can tell it returns a broad contact list.

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?

'All your contacts' implies this is for retrieving the full/unfiltered list, which loosely contrasts with a search tool. However, the description does not explicitly mention contacts_search or any conditions for when to prefer this tool over alternatives, so usage guidance is only implied.

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