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

Annotations already cover the safety profile (destructiveHint=false, idempotentHint=true, readOnlyHint=false), but the description adds genuine behavioural context beyond them: the page shows only one goal at a time, selecting one hides the others, and nothing is deleted. That directly answers the main agent worry for a mutation tool. It does not, however, describe error behaviour for an invalid id.

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 short sentences with no filler. The primary action is front-loaded, and the second sentence exists to answer a specific question (does choosing a goal delete the others?).

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?

An output schema exists, so return values need no explanation, and annotations carry the idempotency and safety profile. For a two-parameter tool, the description supplies the missing semantic context (single-active-goal model, non-destructive behaviour). Nothing essential for a correct call is absent.

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 50%: the boolean 'active' is documented, but the required 'id' is not described anywhere. The description implies id selects the goal and 'turn the current one off' maps to active=false, so it partially compensates, but the parameter half-documented in the schema is the required one, leaving a real gap. Baseline 3 is appropriate.

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: making one goal the one shown on the page, or turning the current one off. The phrase 'without deleting anything' implicitly distinguishes it from delete_goal, but it never names an alternative sibling outright, so it stops short of full differentiation.

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?

Usage is implied by the described effect ('choose which goal the page shows'), and the mutual-exclusivity constraint tells the agent something about when this applies. However, there is no explicit comparison against update_goal or delete_goal, no prerequisites, and no statement of when not to use it.

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