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

Annotations already declare destructiveHint=true and idempotentHint=true, so the safety profile is covered. The description adds genuinely new context: the override propagates to transaction, spending, and recurring results, provider labels are untouched, and no money moves. It does not explain what is lost on 'clear' or whether an overwrite is reversible, which is why it stops short of 5.

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 short sentences, front-loaded with the action, followed by scope-of-effect and a non-monetary clarification. No sentence is redundant and none restates the annotations or schema verbatim.

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?

An output schema exists, so return values need no explanation, and the description covers effect scope and the non-financial nature of the write. For a destructive, idempotent three-parameter write it is nearly sufficient, though it omits whether the prior override is recoverable after 'clear'.

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 33%, but the schema itself carries the conditional requirements in the mode description and enumerates normalizedCode values. The prose adds meaning for 'normalized category' and 'one transaction', but transactionId and the effect of each mode on existing data remain unelaborated beyond the schema.

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 pair ('set or clear') and a specific resource ('your normalized category for one transaction'), so the agent knows exactly what is being written and at what granularity. It is implicitly distinct from the sibling *_get tools, but it never names an alternative or contrasts itself explicitly.

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: an agent can infer this is the tool for overriding a category, and the mode requirements ('set requires transactionId, normalizedCode; clear requires transactionId') come from the schema rather than the prose. There is no explicit statement of when to prefer this over reading raw provider labels or when not to call it.

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