log_spend

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

Annotations already declare idempotentHint=false and destructiveHint=false, and the description is consistent with that. Since there is no output schema, the description usefully adds the return shape ('confirmation with amount, store, date, and item count'), though it says nothing about permissions or duplicate-entry behavior.

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 sentences, front-loaded with the purpose and immediately followed by the triggering condition, with no filler. Every clause carries information.

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 5-parameter mutation tool with no output schema, the description covers purpose, trigger, and the confirmation payload, which is most of what an agent needs. Minor gaps remain around auth/permissions and what happens on repeated logging.

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 80%, so the schema already documents date, store, estimatedTotal, items, and notes. The description adds no parameter-level meaning (units, format, whether items is a count vs list) beyond the schema baseline.

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 — 'Record grocery spending for budget tracking' — which is clearly separable from read-only siblings like get_spend_log. It does not explicitly name a sibling or contrast with log_meal, but the write intent is unambiguous.

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?

'USE WHEN: logging what was spent after a shopping trip' gives a concrete triggering context, which is more than implied usage. It lacks any exclusion or pointer to the alternative (e.g., use get_spend_log to read, log_meal for meals), so it stops short of full routing guidance.

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