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

Annotations already declare readOnly, idempotent, non-destructive, so the safety profile is covered. The description still adds real value the annotations don't: the list action is paginated and returns progress counters (totalLeads, contactedLeads, successfulCalls, missingCalls, onGoingCalls), and campaign scope is limited to call campaigns. It doesn't discuss auth requirements or rate limits, which keeps it below a 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?

Three short sentences, front-loaded with purpose, then actions, then the routing/exclusion note. Every clause carries information: action semantics, returned counters, sibling handoff, and scope boundary.

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?

There is no output schema, so the description bears the burden of return values — it does this well for 'list' by naming the progress counters, but 'get' is only described as 'one campaign by campaignId' with no hint of response shape. For a 6-parameter, low-coverage read tool this is nearly complete, with the 'get' return being the main 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?

With schema coverage at 50%, page, limit, agentId and action carry no schema descriptions and the description compensates only partially — it explains the action enum semantics and that campaignId is needed for get. The 'mode' compact/full parameter and the meaning of agentId and pagination defaults are left entirely to the schema, so baseline 3 is right.

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 ('Read outbound call campaigns of an agent') and enumerates the two supported actions with their identifiers. It also explicitly distinguishes itself from campaigns_write and whatsapp_campaigns_read, so an agent can place it among siblings without opening any schema.

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?

Explicitly routes mutations to campaigns_write ('To change campaigns use campaigns_write') and declares an exclusion ('WhatsApp broadcast campaigns are not covered'), which points the agent at whatsapp_campaigns_read. The action list also makes clear that 'get' requires a campaignId while 'list' is the enumerate path.

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