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

With no annotations provided, the description carries the full burden. It discloses side effects: 'writes a new snapshot, and emits an alert when the delta exceeds the wallet's configured threshold.' It also explains severity levels ('MEDIUM / HIGH / CRITICAL by delta size') and confirms it performs a comparison against a snapshot. It does not mention permissions or reversibility, but for a scanning tool these are less critical. It could say what happens if no alert is triggered, but it is fairly transparent.

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 four sentences, each contributing essential information: the action, the comparison/snapshot/alert mechanism, severity levels, and the parameter behavior plus scheduling context. It is front-loaded with the main action and contains no filler.

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?

The tool is simple (one optional parameter, no output schema, no annotations). The description covers purpose, usage context, behavioral side effects, parameter semantics, and scheduling. Missing is an explicit statement of what the tool returns, but the emphasis is on alert emission. Given the complexity, it is nearly complete.

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 the baseline is 3. The description adds value beyond the schema by explaining the optional behavior: 'Omit 'address' to scan the entire watchlist.' This clarifies the semantics of a single optional parameter, making the parameter more meaningful than the schema alone.

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 opens with 'Scan one or all watched wallets against Polygon RPC', which is a specific verb+resource+scope. It clearly distinguishes this from sibling tools like pg_whale_add, pg_whale_list, and pg_whale_alerts by focusing on the scanning and alerting behavior. It also clarifies the full watchlist vs. single address case.

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 clear context for when to use the tool: 'Designed to be called periodically via SchedulerOracle or a systemd timer.' It implies this is a monitoring/scheduled tool, but it does not explicitly name alternatives or state when not to use it. This is clear context without exclusions.

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