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

Annotations already declare readOnlyHint=false, idempotentHint=false and destructiveHint=false, so the safety profile is covered. The description goes further by explaining the entity model and the two-step activation path, but it never mentions return values (does it hand back the new sender_profile_id?) or duplicate-name behavior.

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?

Two sentences, both earning their place: the first defines the resource and scope, the second gives the follow-up call sequence. Purpose is front-loaded and there is 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 two-parameter creation tool with no output schema, the description covers purpose, entity semantics, and the follow-up workflow. The only real gap is what the call returns and whether the new profile id is directly reusable, which the agent must infer from the mention of sender_profile_id.

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 100% with only two parameters, both already documented ('Profile name, e.g. "Q4 outbound"' and 'Team UUID - get from list_teams'). The description adds no format, constraint, or default information beyond the schema, 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 (create) and resource (sender profile), then defines what the resource is: 'a named group of inboxes (and optionally a LinkedIn account) that campaigns send from.' That definition makes it immediately distinguishable from siblings like update_sender or list_sender_profiles.

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 explicit post-creation workflow steps and names the tools to use next ('put inboxes in it with update_sender (sender_profile_id), then attach it to a campaign with assign_campaign_sender_profile'). This is strong sequencing guidance, though it offers no when-not-to-use condition or prerequisite checks (e.g., whether a team must already exist).

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