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

Annotations already declare readOnlyHint, idempotentHint and non-destructive behavior, so the description's credit comes from adding that no computation is triggered and results are purely previously-saved data. The disclaimer about past results is contextual honesty rather than behavioral detail, but the 'never runs a new backtest' guarantee is a real addition beyond the 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?

Three short, front-loaded sentences with no padding; the core scope comes first. The trailing disclaimer is boilerplate-adjacent but brief enough not to hurt readability.

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?

There is no output schema, but the description doesn't need to explain a return shape beyond naming what is returned (scores). Combined with the read-only annotations, an agent has enough to call it correctly; the unlabeled timeframe enum is the only real residual gap.

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 coverage is 67%: ticker and strategy carry schema descriptions, but the timeframe enum has none. The description adds the constraint that only one ticker is handled per call, which is meaningful, but it says nothing about the timeframe value or the strategy id format beyond the schema's pointer to list_strategies.

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?

States a concrete verb and resource ('stored historical backtest scores for one ticker') with a source reference (alktrading.com/scorecards). It clearly distinguishes itself from the act of running a backtest, though it does not explicitly differentiate from siblings like get_track_record, which a reader might confuse it with.

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 line 'Reads saved results only; never runs a new backtest' gives useful negative guidance about what the tool will not do, but there is no explicit when-to-use or alternative routing (e.g. vs get_track_record or get_signals). Usage must be inferred.

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