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

Annotations already declare readOnlyHint=true and openWorldHint=true, so safety is covered. The description contributes the return content (plan, numbers, slots, fee), which matters because no output schema exists, but it says nothing about freshness of billing data, the billing cycle, or whether fees are prorated.

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 compact sentence that front-loads the resource and lists the payload without filler. Nothing is wasted and nothing needs trimming.

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, enumerating the returned fields is the essential missing piece and the description supplies it. Minor gaps remain around units/currency of the fee and whether usage counters are live, but the core is covered.

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 and the schema is correspondingly empty, so there is no parameter semantics burden to carry. The description correctly implies the call is unconditional with no scoping arguments.

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 names a specific resource (the Bridge plan) and enumerates the exact fields returned: active WhatsApp numbers, slots, and the monthly fee. An agent knows precisely what data this yields, though it does not distinguish itself from siblings like bridge_list_numbers, which likely overlaps on the numbers count.

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 instruction, no prerequisites, and no mention of alternatives such as bridge_list_numbers or bridge_number_status for number-level detail. The usage is only inferable from the resource name itself.

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