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

The description is consistent with the readOnlyHint annotation, indicating a read-only operation. It adds context about returning historical ticks over time. However, it does not discuss behavior around pagination, empty results, or any potential side effects. Given the annotation already covers safety, a score of 3 is appropriate.

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 just two sentences (20 words), capturing the core purpose and a key usage hint. It is front-loaded with the action and resource, containing no filler or repetition. Every sentence earns its place.

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 tool with 3 parameters and no output schema, the description covers the main return fields (equity, totalPnl, netTransfers) and the essential time-bounding parameter. However, it omits guidance on pagination behavior and expected response shape, which would help an agent fully understand usage. The presence of readOnlyHint reduces the gap somewhat.

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 33% (only createdOnOrAfter has a description). The description adds value for this parameter by stating its use for bounding the range. However, the other parameters (page, limit) are left undocumented in both the schema and description, despite their role in pagination. For a low-coverage scenario, more explanation was needed.

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 verb 'Get' and the resource 'historical PnL ticks', specifying the subaccount scope and the fields included (equity, totalPnl, netTransfers). It distinguishes this tool from siblings like get_equity (which likely provides a snapshot) by emphasizing the time series nature.

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 mentions using 'createdOnOrAfter' to bound the range, giving a usage hint. However, it does not explicitly state when to use this tool versus siblings like get_equity or get_portfolio, nor does it provide guidance on pagination (page, limit). More explicit contrasting would improve this dimension.

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