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

Annotations declare the safety profile (readOnlyHint=false, destructiveHint=false, openWorldHint=true, idempotentHint=false), so the description doesn't need to restate it. It does add genuinely new behavioral context: imported campaigns land as DRAFTS and nothing sends without review, the work runs asynchronously in the background, and the call returns a job id rather than the imported data.

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, front-loaded with the purpose, followed by the safety-relevant draft state and then the async/return behavior. Every sentence carries information, with no filler.

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 one-parameter background import with no output schema, the description covers purpose, side-effect semantics, and the return (a job id). The one residual gap is that it doesn't say how to poll or where the job id is consumed, which matters for an async tool.

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?

There is a single parameter with 100% schema description coverage, and the schema already points to where the key comes from (Instantly → Settings → API keys). The description only notes that the key is used without adding format or scope constraints, so the baseline 3 applies.

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?

States a specific verb and resource — importing Instantly.ai campaigns and leads into Emailchaser — which is unambiguous and clearly distinct from the sibling listing/cancellation tools. It stops short of naming any alternative, but the action is concrete enough that no agent would confuse it with list_instantly_accounts or get_lead_finder_import.

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?

Usage is only implied: the mention of an Instantly API key signals the prerequisite, and 'review and launch' implies the follow-up workflow. There is no explicit when-to-use vs when-not-to-use guidance, and no pointer to any tool for checking import status.

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