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

With no annotations, the description carries the full burden. It reveals that the tool can add or update notes and that an empty string clears the note. It also describes the write-tier approval process. However, it does not disclose whether the note is replaced or appended, what the return value is, or any side effects on existing data.

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 description is concise: two sentences plus a brief permission note. It front-loads the purpose and uses examples efficiently. The bracketed permission information, while useful, adds a minor structural distraction but does not harm clarity.

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?

Given the tool has 4 parameters and no output schema, the description provides examples and permission context but lacks details on return values, overwrite vs append behavior, and the exact effect of the 'fiscal_year' parameter. For a simple note update tool, it is adequate but not fully comprehensive.

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 description coverage is 100%, so each parameter is documented. The description adds no extra semantics beyond the schema. The examples in the description illustrate parameter usage but do not provide additional details about constraints or formats.

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?

The description clearly states the action ('Add or update a note') and the specific resource ('P&L account row'). It provides concrete examples of note content, helping the agent understand the tool's use case. However, it does not explicitly distinguish this tool from sibling tools like update_transaction_note, though the resource difference is inferable.

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?

The description gives no guidance on when to use this tool versus alternatives. It does not mention when not to use it or how it relates to similar tools like update_transaction_note. The write-tier approval note is about permissions, not use-case differentiation.

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