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

Annotations declare destructiveHint=true and readOnlyHint=false; the description confirms the destructive 'replace' semantics and explains that an empty note clears the handoff. It adds what the write representatives know: overwriting existing content and how to intentionally clear it. It doesn't mention permissions or failure behavior, but goes well beyond the annotations.

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 front-loaded sentences: the first defines the action and content, the second covers lifecycle relationships and the empty-note rule. Every clause earns its place with no redundancy.

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 two-parameter write tool with destructive hint annotations and no output schema, the description covers action, content expectations, lifecycle interaction, and the clearing behavior. It omits any note about return value or confirmation, but annotations and schema cover the remaining structured detail adequately.

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 goes further by defining what the 'note' parameter should contain and that an empty string is a valid way to clear the note, adding real meaning beyond the schema's maxLength limit. It does not expand on workId, which the schema already documents.

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 ('Replace the handoff note on the Work') plus scope ('so another session can continue it'). It clearly distinguishes itself from sibling tools begin_work and finish_work by describing their differing roles, so an agent can recognize what it does without opening the 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?

Explains the note's intended content (done, remains, files touched, uncommitted changes) and names the related lifecycle tools begin_work (returns it) and finish_work (clears it). It also gives an operational rule: pass an empty note to clear it. There is no explicit 'use this when...' trigger, but context is clear.

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