stock_bj_a_spot_em

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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is covered. The description adds marginal context by specifying the return type (pandas.DataFrame) and the source URL, but it does not disclose potential latency, data delay, or other behavioral nuances. No contradiction with 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 extremely concise and front-loaded, stating the core purpose first, followed by the source URL and return type. Every line earns its place, with no redundant text. It is very easy to scan.

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 zero-parameter, read-only spot quote tool, the description covers key aspects: data source, market segment, data type, and return format. The explicit return type compensates for the lack of an output schema. It does not detail the DataFrame columns, but this is a minor gap for such a simple fetch operation.

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 the input schema correctly reflects this with an empty properties object (100% schema coverage). Since there are no parameters, the description does not need to explain them. The baseline for 0 params is 4.

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 provides real-time quotes (实时行情) for Beijing A-shares (京 A 股) from East Money (东方财富网), with a source URL. This distinguishes it from sibling spot tools like stock_cy_a_spot_em and stock_sh_a_spot_em. However, it lacks an explicit action verb, using a noun phrase instead.

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 provides no guidance on when to use this tool versus alternative spot quote tools. It does not mention any exclusions, preconditions, or alternative tools. An agent must infer usage from the tool name alone, which is insufficient given the large sibling set.

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