Cohort Daily Performance

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

Annotations already establish that this is a read-only, idempotent, non-destructive operation. The description adds useful behavioral context beyond those hints by specifying the 30-day range limit and describing the returned metrics, which is especially valuable given there is no output schema.

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 compact sentences cover purpose, output contents, use case, and a key limit with no filler. The most essential information is front-loaded in the first sentence, making it easy for an agent to quickly determine whether to invoke this tool.

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 read-only query tool with no required parameters, the description is largely complete: it states what the tool returns, who it covers, and its range constraint. It does not describe default time-window behavior or format switching, but those are covered by the input schema, so only minor contextual gaps remain.

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 100%, so the schema already documents all four parameters including defaults, patterns, and the override relationship between startTime and since. The description adds only the general 30-day max, which restates the schema's 'max 30d' note, so no significant new parameter meaning is provided.

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 a specific verb and resource: 'Get historical daily performance statistics for all trader cohorts.' It further clarifies the scope by listing the exact returned metrics (PnL, volume, trade counts, active trader counts per tier), making it clearly distinct from sibling cohort tools such as pulse_cohort_summary or pulse_cohort_positions.

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 a clear use case: 'Use this to track the consistency and profitability of different groups over time.' It also communicates an important constraint ('Max range is 30 days'). However, it does not explicitly mention when to prefer alternative tools, such as pulse_trader_daily_stats for individual trader statistics.

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