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

With no annotations, the description carries the full behavioral-load and usefully discloses that this performs no sending and consumes no credits. However, it does not address authorization requirements, whether campaign_id changes defaults or overrides other parameters, or any other side-effect details beyond the no-send/no-credit note.

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 three compact sentences with no wasted text. The core purpose is front-loaded, the campaign_id usage instruction follows, and the safety note is placed at the end.

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 five-parameter preview tool with no annotations and no output schema, the description gives enough to understand the high-level operation and its no-side-effect nature. It is not complete enough to guide correct use of agent_id versus campaign_id, or the exact_text parameter, and the nested sample object is only described in the schema.

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 only 20%, so the description must compensate. It adds useful meaning for mode (AI from the agent vs fixed text with placeholders) and campaign_id (use saved settings), but leaves agent_id unexplained and does not clearly name exact_text or explain how it relates to the fixed-text mode.

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 states a specific action and resource: rendering the first LinkedIn message sent after an invite is accepted. It also distinguishes the AI and fixed-text variants, but it does not explicitly name the close sibling preview_linkedin_followup, so the sibling differentiation is good but not fully explicit.

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?

The description gives one concrete usage instruction: pass campaign_id to use saved settings. It also clarifies that this is a preview with no sending and no credits, but it does not state when to choose this over the campaign invite preview or the generic LinkedIn follow-up preview.

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