Market Snapshot

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

With no annotations, the description carries the full burden and delivers real behavioral context: an output contract (name/price/change/time per item), session-state labeling for US indices, a null-instead-of-guessing rule for unreliable A-share turnover, and a no-recommendation disclaimer. It omits auth/rate-limit behavior, keeping it short of a 5.

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?

Front-loaded with the payload contents, then the output contract, then caveats. The data-source line and tested-date stamp are defensible for a live-quote tool. Slightly dense but every sentence carries weight.

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?

An output schema exists, so return values need not be restated, yet the description usefully supplements it with the null-handling and session-label conventions an agent needs. Given a parameterless, single-call tool, this is close to complete.

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?

Zero parameters, so the baseline of 4 applies. The description sensibly uses that space for the output contract rather than fabricating parameter guidance.

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 specific resource (market snapshot) and enumerates exactly what it returns: four A-share indices, three US indices, WTI crude, COMEX gold, offshore RMB. This scope enumeration clearly differentiates it from narrower siblings like quote and close_recap without opening either schema.

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 ties itself to two named workflows (laogu-morning daily brief / laogu-close review), which implies the usage context. However, it never explicitly contrasts against sibling tools such as quote or fund_flow, nor states when this broad snapshot is the wrong choice. Usage is implied rather than stated.

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