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

Annotations establish a non-destructive write (readOnlyHint=false, destructiveHint=false, openWorldHint=false), and the description adds the non-obvious ordering behavior: appended to the end, or at the top when the user chose 'New first'. That ordinal side effect is genuine extra context, though auth/permission needs go unmentioned.

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, front-loaded with the action and scope, then the placement rule and style constraint. No wasted words.

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 small 3-param mutation tool with no output schema, the description covers where the item lands, its optional sphere/star, and the expected tone of the content. Only minor gaps remain, such as the 1000-character ceiling already carried by the schema.

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?

The schema documents 'sphere' and 'important' but leaves 'text' bare, and the description compensates by framing it as the user's own short wording. It also maps the plain-language 'starred' onto the 'important' parameter and explains the sphere placement, adding meaning beyond the schema.

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?

Specific verb+resource ('Add one focus point to the Focus section') that separates it from add_goal, add_task, and add_sphere. It states scope and optional modifiers clearly, though it doesn't name a sibling it is *not* to be confused with.

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 a style instruction ('Keep it short, in the user's words') but no when-to-use/when-not guidance and no pointer to alternatives such as update_focus_point for editing an existing point or add_goal for goals. Usage is only implied.

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