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

With destructiveHint=true and readOnlyHint=false already declared, the description adds real behavioral context: a two-phase approval flow (implied by confirmation_token), the default 4-step workflow when steps are omitted, and default-list creation side effects. It doesn't spell out irreversibility or auth requirements, so not a full 5.

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 core verb is front-loaded and each sentence carries operational content, but the description is long and re-states at least one schema detail (the {FirstName}/{LastName}/{Company} variables). Mostly earned, slightly padded.

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 7-parameter, no-output-schema mutation tool, it covers the approval workflow, list-resolution defaults, workflow defaults, and the negative constraints. It leaves the confirm-preview mechanics and confirmation_token acquisition flow implicit, which is the only material gap.

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 coverage is 100% so baseline is 3, but the description adds resolution logic the schema lacks: with agent_id and no list_id use the agent's destination list, otherwise the product default list is assigned/created, and an explicit different list retargets a draft agent only after approval. The personalization-variable constraint is repeated from the schema, so not a 5.

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 ('Create a draft campaign in the selected product') and immediately scopes it as a draft with an approval gate. An agent can distinguish this from enable_campaign, update_campaign_workflow, or update_campaign_settings because the description says it creates rather than mutates or activates.

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?

Explicit when-to-use and when-not-to-use: 'First show the exact campaign... for approval' and 'Never activate, discover, enroll, or send.' It also routes alternative cases (agent_id with/without list_id, custom vs default workflow_steps), leaving little to inference.

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