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

Annotations only declare the safety profile (readOnly false, idempotent false, destructive false). The description goes well beyond by disclosing the key side effect that on a live campaign the change applies to every enrolled recipient's next unsent step, the validation gate that must pass or nothing is saved, and the confirm-flag guard for hard-to-undo actions.

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?

Core purpose is front-loaded in the first clause, followed by side effects, then token/validation detail. It is dense and slightly run-on across clauses, but nearly every sentence carries actionable constraint information rather than 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?

With 6 parameters at full schema coverage, no output schema, and no nested objects, the description covers what is missing from structured data: live-campaign propagation, validation failure behavior, token syntax, and where to preview. An agent has enough to invoke it correctly.

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 real meaning: subject is step-1-only, body personalises via named {{tokens}}, and website copy must pass specific checks (no links, bare domains, stock phrases, unknown tokens, empty offer). Those constraints are not in the schema.

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 (edit) and resource (one step of a campaign's email sequence) plus the fields it mutates (subject, body, delay). It is clearly separable from update_campaign_settings and rename_campaign by naming the step-level granularity.

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?

Gives clear context for when to use it (editing a step's subject/body/delay, with an explicit note that subject applies to step 1 only) and routes to get_campaign and preview_campaign_step for tokens/preview. It does not explicitly exclude or contrast with update_campaign_settings for non-step edits, so it falls short of a full when/when-not statement.

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