contacts_list

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

Annotations already declare readOnlyHint=true, destructiveHint=false, and openWorldHint=true, so the safety profile is covered. The description adds the transport endpoints (POST path, gRPC method, socket channel) and the word 'page', which implies paginated reads, but it says nothing about ordering, default/max page size, or auth requirements — modest added value above the annotations.

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 compact and front-loaded — the core purpose leads, with transport details relegated to a parenthetical. The triple endpoint notation is borderline noise for an agent, but it is contained and does not bury the main statement.

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 no output schema and three undescribed parameters, the description should carry pagination and scoping semantics; it instead stops at 'A page'. Nothing wrong is stated, but an agent lacks what it needs to page correctly or choose this over contacts_sync/search.

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%: page, limit, and channelId have only examples and no textual semantics. The description partially compensates by implying the channel scoping ('a channel's contacts') and pagination ('a page'), but it never explains page numbering, default or maximum limit, or how page/limit interact.

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 phrase 'A page of a channel's contacts' identifies the resource (contacts, scoped to a channel) and implies pagination, but it is a noun phrase describing output rather than a stated action, and it distinguishes nothing from siblings like contacts_get, contacts_search, or contacts_sync. An agent can guess the intent, but it must consult the name and schema to confirm this is the paginated listing operation.

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, no prerequisites, and no mention of alternatives such as contacts_search (querying by term) or contacts_sync (bulk sync). The agent is left to infer selection from the tool name alone.

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