Re-fetch and re-summarise an item

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

Annotations only say non-readonly, open-world, non-idempotent, non-destructive; the description adds genuinely new behavior: what is preserved (note, favorite, share history, chosen folder), the model-failure fallback that keeps the existing summary, cost bounds (one page fetch, at most one model call), a rate limit of once per minute per item, and three explicit failure modes.

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?

Front-loaded with the action, then routing, then preconditions, then preservation and limits — a logical order. It is a dense single paragraph, slightly thick with clauses, but nearly every sentence carries non-redundant operational 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 a one-parameter mutation tool with no output schema, the description covers the full picture: what changes, what survives, cost/rate bounds, fallback behavior and failure conditions. Nothing an agent needs to invoke it correctly 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 integer id is already documented, so the schema does the heavy lifting. The description still adds a real constraint beyond the schema: the id must reference an item outside the trash and must be restored via driftnet_update_item first.

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+resource pair: re-fetches an item's page and regenerates summary, tags and rating. It explicitly contrasts with driftnet_save_link (link not yet catalogued) and driftnet_enrich_item (own summary for a queued item), so an agent can pick it without opening siblings.

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 the trigger condition ('when a card is empty or stale, e.g. saved behind a login wall or while the page was down') and routes two adjacent cases to their correct sibling tools by name. Exclusions are stated as well: the id must be outside the trash, restore first via driftnet_update_item.

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