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

With no annotations provided, the description carries the full disclosure burden and explicitly states 'Read-only, free,' telling the agent this is a safe, non-mutating call. It also reveals important behavioral scope: results include everyone contacted, not just those who replied. Pagination and rate limits are not mentioned, but these are minor for a parameterless list operation.

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?

Three short sentences deliver the core definition, the key scope distinction from CRM leads, and the safety/cost profile with no filler. The most important information is front-loaded.

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 parameterless read-only list tool with no output schema or annotations, the description is complete enough to invoke correctly: it states what is returned, how results are organized, how it differs from an alternative, and that it is free and safe. Minor return-format details could be added but are not necessary for correct invocation.

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 input schema has zero properties, so there are no parameter semantics to clarify. The description still adds value by explaining what the returned cards represent and how they are grouped, which meets the zero-parameter baseline.

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 uses a specific verb ('List') and resource ('communication cards'), then defines the exact granularity: one card per campaign and per SDR search with outbound counters. It also distinguishes itself from CRM leads by clarifying this is the full outbound stream, not just people who replied.

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?

It gives a clear selection context: use this when you need the full outbound stream including non-responders, and it explicitly contrasts CRM leads as containing only people who answered. It does not name a sibling tool directly, but 'CRM leads' clearly maps to crm_list_leads, which is sufficient guidance.

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