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

Goes well beyond the annotations: it discloses optimistic-concurrency semantics, the exact failure code UPDATE_REVISION_MISMATCH, its cause (another writer), and the recovery path (a fresh get_page). Annotations only give destructiveHint/idempotentHint, so this adds substantial operational context.

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 tight sentences, front-loaded with the two update modes, then the concurrency precondition, then the publish boundary. Every clause carries distinct information with no repetition of the schema.

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 destructive, nested-object mutation with no output schema, the description supplies permissions, concurrency rules, error recovery, and the publish hand-off. 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%, so the baseline is 3; the description earns extra credit by explaining the conditional relationship between content and expectedUpdateRevision and what happens on a stale revision, which the schema only states as a plain requirement.

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 web part page') and immediately scopes it into two modes: metadata (title/icon) and content. This distinguishes it cleanly from get_page, create_page, and publish_page without the agent needing to open 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?

Explicitly routes the agent: content updates require expectedUpdateRevision from get_page, and 'Publishing is separate: publish_page makes changes public' names the sibling and the condition that selects it. The contribute-access prerequisite is also stated.

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