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

Annotations already cover read-only and non-destructive behavior. The description adds useful context beyond that: the report bundles period cards, settlement waterfall, freshness caveats, and quote_rules, and signals that it is a single consolidated call. This gives the agent a meaningful picture of what to expect.

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 compact and information-dense. It front-loads the canonical purpose, lists the key report contents, and closes with an explicit usage preference. Every clause earns its place without fluff.

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 report tool with no output schema, the description gives enough high-level content and usage context to guide invocation. It could be more complete by explaining quote_rules or the meaning of 'freshness caveats,' but overall the agent can infer the tool's role and scope.

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 description provides no parameter-level guidance. Schema coverage is 75%, but the 'currency' parameter is undocumented and the description does not clarify it or add meaning to any parameter. The tool relies entirely on the input schema, which has a notable gap.

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 identifies the tool as the canonical account overview, listing its main components (period cards, settlement waterfall, freshness caveats, quote_rules). It is distinct from the many specialized pnl_* siblings by emphasizing 'ONE call' and the canonical status, though it does not explicitly name an alternative tool.

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?

It gives explicit guidance to prefer this tool for 'how is the account doing' questions, which is a clear usage signal. However, it does not state when not to use it or explicitly compare against alternatives like pnl_breakdown or pnl_summary, so some inference remains.

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