Get PnL

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

Annotations already establish readOnlyHint=true and openWorldHint=false, so the safety profile is covered. The description adds meaningful context about which PnL components are included and that results are bucketed by day, but says nothing about default date range, aggregation currency, or behavior when no data exists in the window.

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?

A single front-loaded sentence with no waste, listing the PnL components compactly. The phrasing 'This agent's' is slightly ambiguous about whose PnL is returned, which costs a point but not clarity of the core content.

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?

With only two optional params and a read-only annotation, the definition is close to sufficient, and no output schema means return values needn't be explained. However, the entirely optional date range leaves a real gap: the agent cannot know the default window or the response shape without calling it.

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% with clear YYYY-MM-DD format notes on both bounds, so the schema carries parameter meaning. The description contributes the additional semantic that the output is grouped 'by day', which tells the agent how the range bounds map to result granularity.

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 names the resource (daily PnL) and enumerates the components returned (realised, unrealised, fees, funding), so an agent knows what it retrieves. It lacks an explicit verb and does not contrast itself with siblings, but the resource is specific enough to distinguish it from get_venue_rules or list_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?

There is no guidance on when to call this versus other tools, and no statement about what happens when 'from'/'to' are omitted even though both are optional. An agent must infer the default window and cannot tell whether this is the right tool for historical versus current PnL.

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