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

Annotations already declare idempotentHint=true, destructiveHint=false and openWorldHint=false, so the safety profile is covered structurally. The description adds no behavioral context of its own (what happens if the key is unknown or already unmarked), and instead spends its text on amount/date formatting that this tool never uses.

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?

The core action is correctly front-loaded in the first clause, but the remaining two clauses explain minor-unit amounts and YYYY-MM-DD/YYYY-MM date conventions — none of which exist as parameters on this tool. That is inherited boilerplate that consumes most of the description without earning its place.

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, annotation-covered, output-schema-less tool the definition is close to sufficient, but it omits any statement of behavior on an invalid or stale key and pads with irrelevant formatting rules instead of the missing behavioral detail.

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?

The single `key` parameter has 0% schema description coverage, so the description must carry it. '(its key)' usefully tells the agent the value is the key returned by mark_bill, but it gives no format, length, or tolerance details, leaving the required input only partially explained.

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?

Names a specific verb (Remove) and the exact state being undone (a mark made with mark_bill), tying itself to its inverse sibling rather than restating the tool name. An agent can distinguish it from dismiss_bill/undismiss_bill/delete_transaction without opening any 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?

Usage is only implied through the inverse relationship: you call this to undo mark_bill. There is no explicit statement of when this is appropriate versus undismiss_bill or delete_transaction, and no when-not or error-condition guidance.

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