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

Annotations already declare non-read-only, non-destructive, non-open-world behavior. The description adds valuable context beyond annotations: what the note contains, that re-filing adds tags to the same note instead of creating a copy, and that missing tags are created. It does not describe permissions, errors, or return behavior, and the idempotentHint=false annotation is in slight tension with the no-copy re-filing behavior, though not a direct contradiction.

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 compact sentences front-load the main action and then cover the important edge cases. There is no filler or repetition.

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 simple two-parameter mutation with annotations covering its safety profile and no output schema, the description supplies the key transformation, note contents, tag-creation side effect, and repeat-filing behavior. Nothing essential for correct invocation is missing.

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 already documents the URL source and the tag array including maxItems. The description adds behavioral meaning about tags being created if missing, but does not add parameter syntax or format details beyond what the schema provides, so the 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 ('file article') and describes the concrete transformation: the article becomes a note under the given tags, holding its text, link, and summary when available. This clearly distinguishes it from read_article, list_notes, and other siblings by outcome.

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?

The description implies this is for saving feed articles into tagged notes, and the schema notes the URL comes from list_feed_items. However, it does not explicitly say when to choose this over capture or update_note, nor does it state 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.