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

Annotations already flag destructiveHint=true and idempotentHint=true; the description adds meaningful context by spelling out that markdown overwrites the entire body and by stating the return value (document id + URL). It does not say what happens if neither title nor markdown is passed, nor whether omitted fields are preserved, which would be the last piece of behavioral clarity for a destructive update.

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 clauses, front-loaded with the action and its target, followed by the required parameter and the destructive-replacement warning. No filler sentences.

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 three-parameter mutation tool with no output schema, the description covers the action, the required input, the destructive replace semantics, the sibling alternative, and the return shape. An agent has everything needed to call it correctly.

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 67%, with title and documentId undocumented in the schema; the description compensates by marking documentId as required and framing title/markdown as an either-or pair. It adds the crucial replace-vs-append semantics for markdown beyond what the schema says. It stops short of mentioning the length limits the schema enforces.

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 ('Update a Library document') plus the exact fields it can replace (title and/or markdown body). It also explicitly positions itself against the sibling stride.append_to_document, so an agent can tell the two apart without opening a schema.

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?

Names the alternative tool and the condition that selects it: 'Markdown REPLACES the whole body; use stride.append_to_document to add to the end instead.' It also states the required parameter and that at least one of title/markdown should be supplied, leaving nothing to inference.

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