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

Annotations already declare readOnlyHint, idempotentHint, and non-destructive behavior. The description adds meaningful details beyond those annotations, such as the credit balance being 'available + held' and the presence of 'evidence-based stats.' This gives the agent a more concrete picture of what the operation exposes without contradicting 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?

The description is a single sentence that front-loads the key information: whose account, what fields, and the balance breakdown. Every word earns its place, and there is no redundant repetition of the tool name or title.

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 read-only, zero-parameter account summary tool with an output schema, the description is complete enough. It names the resource and the key data elements, while the output schema can cover detailed return structure. No critical contextual gap remains for an agent to invoke it correctly.

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?

The tool has zero parameters and schema coverage is 100%, so there is no parameter semantics gap for the description to fill. The description correctly focuses on the return content rather than parameters. The baseline of 4 for a no-parameter tool is appropriate because there is nothing more the description could add here.

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 identifies the resource—your market account—and the specific information returned: participant id, credit balance split into available and held, and evidence-based stats. It lacks an explicit verb like 'gets' or 'returns,' but the title and readOnly annotation make the intent unambiguous. It is distinguishable from sibling market tools because it is specifically about the caller's own account.

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 phrase 'Your market participant id, credit balance...' implies this is the tool to call when you need your own account summary. However, it does not explicitly state when to use it versus alternatives, and no sibling distinction or exclusion criteria are provided. The usage context is clear enough by implication but not explicitly guided.

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