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

Annotations already declare readOnlyHint=true and destructiveHint=false, so safety is covered, but the description adds meaningful context beyond them by disclosing the shape of the response, including role-family fields (agentType, customer, instanceCount, siblings) and the multi-tenant SaaS scenario they surface. It stops short of 5 because it omits any note on permissions or size/cost of the fetch.

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 sentences, with the core purpose front-loaded, and the role-family explanation earns its length by clarifying the return payload. Slightly verbose on the SaaS framing, but no wasted 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 read-only get with 100% schema coverage and no output schema, the description carries the return-value burden well by naming the fields an agent will receive. What remains thin is routing and permission context, which keeps it from a 5.

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%, so both agentId and customerId are already documented in the schema, and the description adds no parameter-level detail or format hints. Baseline 3 is appropriate when the schema does the heavy lifting.

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 ('Get the full details of an agent') and enumerates what is returned (system prompt, configuration, metadata, role-family fields), which clearly separates it in granularity from list_agents and get_agent_status. It does not explicitly name a sibling it competes with, so it stops short of a 5.

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?

There is no when-to-use, when-not-to-use, or alternative-routing guidance. An agent must infer from 'full details' that this is the single-agent fetch versus get_agent_status or analyze_agent, and nothing clarifies when the customerId override is appropriate beyond the schema note.

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