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

Annotations already declare destructiveHint=true, idempotentHint=false, and openWorldHint=true, so the safety profile is covered. The description adds genuinely new behavioral context: 'Only the fields given change' discloses partial-update semantics, and the status sentence discloses runner side effects (stopping/starting execution). It stops short of covering reversibility or permission requirements.

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 the field list, then status semantics, then the partial-update guarantee. No filler and every sentence carries distinct information.

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 an 8-parameter mutation tool with no output schema and a destructive annotation, the description covers the field set, status side effects, and partial-update behavior. It leaves out reversibility and any permission/authorization notes, which would be the remaining 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 description coverage is only 25% (just agent_id and goal_id), so the description must compensate, and it does: it names every remaining field (title, objective, success criteria, plan, iteration cap, status) and explains the four status values' effects. It does not clarify constraints like the 200-iteration cap or plan item limits, which the schema carries silently.

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?

The description opens with a specific verb and resource ('Change a goal's...') and enumerates the mutable fields, so an agent knows exactly what the tool mutates. It does not explicitly distinguish itself from siblings like archive_agent_goal, update_org_goal, or create_agent_goal, which keeps it from 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?

It gives real guidance on the status values ('paused stops its runner, active starts it again, completed and archived end it'), which tells an agent how to use the enum meaningfully. However, it never says when to prefer this tool over archive_agent_goal or update_org_goal, so the alternative-selection guidance is only implied.

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