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

With no annotations, the description carries the full behavioral burden, and it delivers: it states this is a read of the parent document rather than history/events, notes zero research token cost, and explains the special 'not recorded' semantics for collateral fields. This is genuinely useful non-obvious behavior beyond the schema.

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 dense but every sentence earns its place: it front-loads what is returned, then gives usage timing, then explains a critical data interpretation nuance, then states cost. There is no filler or repetition.

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?

Even without an output schema, the description enumerates the key returned fields, explains the special-case 'not recorded' values, states cost, and gives usage context. For a single-parameter status-query tool, an agent has everything needed to invoke it correctly and interpret its results.

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 100%, and the schema already documents backtest_id as required and user-owned. The description adds context about when to use the tool but does not add new parameter format details. Baseline 3 is appropriate because the schema handles parameter semantics.

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 opens with a specific verb and resource: 'Return the parent backtest document's status, error, interval, timestamps, elapsed time, and completed statistics.' It also explicitly distinguishes itself from query_backtest_history by stating it works 'without reading history/events.' This leaves no ambiguity about what the tool does or how it differs from its sibling.

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?

It gives explicit placement guidance: 'Use immediately after backtest_portfolio or before query_backtest_history so ERROR/PENDING/RUNNING states are explicit.' This tells the agent both the trigger and the sequencing relative to related tools, which is more than enough to select the correct tool.

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