pnl

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

No annotations are provided, so the description carries the full burden. It does add useful behavioral context by specifying 'mark-to-market' and enumerating the report contents, which sets expectations for the valuation method and output. However, it does not mention permissions, data freshness, or any side effects, which is a notable gap for a tool with no annotations.

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 a single, well-structured sentence that front-loads the purpose and lists the key report components. Every word earns its place, with no redundancy or 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?

Given that the tool has an output schema (which covers return values) and a single simple parameter, the description provides most of the necessary context: what the report contains and the valuation basis. It lacks some details like error scenarios or account identification format, but it is reasonably complete for the tool's simplicity.

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 input schema has one required parameter 'account' with zero description coverage. The tool description mentions 'for an account' but does not explain what the account parameter should contain (e.g., ID, name, format). This adds only minimal meaning beyond the schema, failing to compensate for the lack of parameter documentation.

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 that the tool generates a mark-to-market P&L report for an account and lists the specific components included (positions, unrealized P&L, cash, total equity). This is specific enough to distinguish it from sibling tools like summary or performance.

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?

There is no guidance on when to use this tool versus alternatives. The description simply states what it does without any 'use this when' or comparison to similar tools, so the agent gets no explicit direction on selecting this over others.

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