market_get_portfolio_chart

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

With no annotations, the description carries the full burden of behavior disclosure. The verb 'Get' implies a read operation, but the description does not clarify whether the data is historical, real-time, cached, or what the response contains besides 'chart data'. It lacks any mention of output format, units, or other behavioral traits.

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 concise sentence, 'Get portfolio performance chart data', with no redundant or wasteful wording. It is appropriately sized for a tool with two parameters and no complex behaviors, earning a perfect conciseness score.

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?

The tool is simple with two well-documented parameters, but the description does not explain what the returned chart data looks like (e.g., time series points, arrays, timestamps) or how it relates to the portfolio. With no output schema and no annotations, the agent lacks sufficient context to understand the return value, making this incomplete.

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 both parameters ('type' as 'Chart time period' and 'shareToken' as 'Portfolio share token') documented. The description adds no extra meaning beyond the schema, so the baseline of 3 is appropriate.

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 tool retrieves chart data for a portfolio, using the verb 'Get' and the resource 'portfolio performance chart data'. It is specific enough to convey the core function, but it does not distinguish this tool from similar siblings like portfolio_get_performance or market_get_portfolio_coins, which also deal with portfolio 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, such as portfolio_get_performance for summary performance or market_get_portfolio_coins for coin-level data. The description provides no context, exclusions, or mention of alternative tools, leaving the agent to infer usage based solely on the name.

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