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

Beyond the annotations (readOnlyHint=false, destructiveHint=false), it discloses idempotency ('saving twice is harmless') and the side effect of appearing in my_recipes — genuinely useful behavioral context for a mutation tool. It doesn't mention any permission or quota constraints, but for a low-risk save that is a minor omission.

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 with no wasted words: the action and its effect lead, the usage trigger follows, and the idempotency note closes. It is front-loaded and appropriately sized for a single-parameter tool.

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?

With one required parameter at full schema coverage, no output schema, and safety already declared by annotations, the description covers everything an agent needs: the effect, the trigger, and the repeat-call behavior.

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 coverage is 100% and the schema itself explains where recipeId comes from, so the description adds no parameter detail beyond that. Baseline 3 is appropriate when the schema carries the full burden.

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 ('Save a recipe to the user's own collection') plus the observable effect ('shows up in my_recipes'), which clearly separates it from siblings like get_recipe, my_recipes, and add_items.

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 an explicit trigger condition with concrete user utterances ('save that one', 'add it to my recipes'), so an agent can recognize when to call it. It stops short of naming an alternative tool or stating when not to use it, so it isn't a full when/when-not specification.

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