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

Annotations declare destructiveHint=true and readOnlyHint=false; the description adds valuable context about the write-tier approval process and the constraint that it cannot look up transactions by description. This goes beyond what annotations alone provide and does not contradict them.

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 well-organized with clear sections for purpose, routing, and approval. It is slightly verbose in the approval block but each sentence carries necessary operational detail. Front-loading the core purpose and routing makes it efficient.

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's complexity (required params, approval flow, no output schema), the description covers the essential prerequisites, routing, and behavioral constraints. An agent has everything needed to call it correctly without missing context.

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 parameters are already documented. The description adds routing context for transaction_id (must come from get_transactions/search_transactions), which is useful beyond the schema, but it does not elaborate on note or companyId semantics beyond the schema definitions.

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 verb (add/update) and resource (note on a specific transaction), and gives usage context ('Use after pulling transactions'). However, it does not explicitly distinguish this from sibling tools like update_finance_note or update_transaction_account, so it falls short of the full 5.

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?

Provides explicit routing instructions: 'Call get_transactions or search_transactions first to get the transaction_id — this tool cannot look one up by description.' It also specifies the approval workflow, making when-to-use and prerequisites unambiguous.

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