prepare_campaign_messages

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

Annotations only give a coarse profile (non-read-only, non-destructive, non-idempotent), so the description carries real added value: it discloses the skip rules, that running it mutates state by marking the campaign ready, and that no bulk sends, browser, scraping, or LLM calls occur. The write-to-non-idempotent combination is consistent with the annotations and is usefully explained.

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?

Four dense sentences that front-load what is prepared before the safety caveats, with almost no filler. The single blemish is the trailing 'even when draft_mode is off', which spends words on a parameter that is not in the schema.

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?

An output schema exists, so return values need not be described, and the description covers the mutation, the filtering rules, and the no-side-effect guarantees an agent needs before invoking. The unresolved 'draft_mode' reference and the total lack of parameter semantics are the only meaningful gaps for a 3-parameter 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?

Schema description coverage is 0%, so the description must compensate, yet it explains nothing about 'account' or 'campaign_id' and only partially touches 'max_messages' via 'at most 20'. Worse, it references a 'draft_mode' switch that does not exist among the three declared parameters, adding confusion rather than clarity.

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 ('Prepare ... personalized private-message drafts') plus the target population ('eligible new/qualified leads on an active account'), so an agent knows exactly what is produced. It stops short of naming how it differs from the close siblings preview_campaign_message and prepare_outreach, so it is clear but not sibling-differentiating.

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 supplies eligibility filtering rules ('skip opt-outs and prior pending/delivered members') and a downstream workflow ('review every exact payload and approve each draft individually'), which implies when to reach for it. However it never states when to use this instead of preview_campaign_message or prepare_outreach, and gives no explicit exclusions or prerequisites, leaving the routing decision to inference.

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