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

Annotations already declare readOnlyHint=true, destructiveHint=false, openWorldHint=false, so the safety profile is covered and the description does not contradict it. It adds a genuinely useful capability note — 'Works on long documents in full' — which tells the agent no chunking or truncation workaround is needed. It stops short of latency, cost, or output-delivery detail, so not a 5.

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 usage trigger before the exclusion, and every clause carries information (purpose, supported document types, style intents, alternative tool). No filler.

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?

An output schema exists so return values need not be described, annotations cover the read-only/no-side-effect profile, and both parameters are fully documented. The remaining operational facts an agent needs (when to call it, what not to use, capability on long inputs) are all present.

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%, so baseline is 3; the description goes slightly beyond by mapping natural-language user intent ('a TL;DR, key points, action items') onto the style values, helping the agent choose a style from the request rather than from the enum alone. It still doesn't explain what 'detailed' produces versus 'tldr' in output terms.

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 ('summarize one of their Xenition documents, notes or research') with the output shapes enumerated (TL;DR, key points, action items, fuller summary). This distinguishes it cleanly from siblings like edit_artifact, extract_from_artifact and repurpose_artifact without the agent needing to diff schemas.

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?

Explicit trigger ('Use this when the user wants a summary'), an explicit exclusion ('Do not use to change the document') and a named alternative ('use edit_artifact'). Nothing about when to pick this tool is left to inference.

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