analyst_monthly_performance

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

With no annotations, the description carries the full transparency burden. It discloses the exact time-window enforcement (DATE_TRUNC('month')), the guaranteed presence of all 10 analysts, empty-array behavior, null conditions for winRate and avgReturn, and the data source (signal_history table). This is comprehensive behavioral disclosure beyond the name alone.

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 dense but every sentence earns its place. It front-loads the core summary, then precisely explains edge cases (null values, empty arrays, month bucketing). Despite its length, there is no redundancy or 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?

For a zero-parameter tool with no output schema, the description fully explains the return semantics: metrics, null conditions, analyst coverage, and time-window guarantees. An agent has everything needed to interpret results and route queries correctly, even amid many sibling analyst tools.

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?

The tool has zero parameters, so there is nothing for the description to add. Baseline for 0 params is 4; the description correctly adds no parameter information because none exists.

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 tool returns a monthly performance summary for all analysts over the last 6 months. It names the exact metrics (win_rate, avg_return, total_signals) and distinguishes itself from sibling analyst tools by specifying the fixed window, canonical analyst list, and empty-array behavior.

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 explicitly gives example use cases: answering 'How did WhaleWatch perform in May?' or 'Who was the best analyst last month?'. It does not name alternatives or state when not to use this tool, so it does not fully earn a 5, but the use context is clear.

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