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

Beyond the annotations (readOnly=false, destructive=false), the description discloses the draft lifecycle and the tool required to publish — genuinely useful state information. It says nothing about whether targets are validated, what happens to an existing plan, permissions, or the response payload, and the meal-replacement behavior appears only in the schema.

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 followed by the lifecycle caveat. Nothing redundant; every clause adds decision-relevant 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 write tool with a nested meals array and no output schema, the description covers creation intent and publication state but leaves the bulk of the contract (targets, meal semantics, replacement behavior) to the schema. Adequate, but thin for its complexity.

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% on 8 parameters, so the description needs to carry more weight. It clarifies student_id as optional-with-consequence (template mode), but the four target_* parameters, notes, and meal structure get no meaning from the description at all.

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?

A concrete verb plus resource ("Writes a diet plan with meals and foods") with the student_id/template distinction spelled out, which is more than a restatement of the title. It does not explicitly separate itself from update_diet_plan or copy_diet_plan, which an agent must infer from the create semantics.

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?

"Or a template without it" states the condition for omitting student_id, and "It starts as a draft: activate_diet_plan publishes it" names the follow-up tool and the state the object lands in. No explicit when-not or prerequisites (e.g. student must exist, foods come from search_foods), so not a 5.

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