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

Annotations already declare readOnlyHint, idempotentHint, non-destructive and closed-world, so the safety profile is covered. The description adds real value by disclosing the return content (stage classification plus same-stage listed competitors), which matters because there is no output schema. It does not say what happens when a stock is unclassified or outside covered chains, nor how competitors are selected.

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?

Two compact sentences: the first states what is returned, the second anchors it with a concrete example. Nothing is padded, and the core purpose is front-loaded. The example is slightly redundant with the first sentence but genuinely aids interpretation of '공정 단계'.

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 low-complexity, single-parameter lookup with full annotation coverage and no output schema, the description is close to sufficient: it conveys both the classification result and the peer list. The remaining gap is edge-case behavior, such as unclassified stocks or empty competitor sets, which an agent might need before relying on the result.

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?

There is a single parameter with 100% schema description coverage, including the 6-digit code format and a pointer to search_stocks when unknown, so the schema carries the burden. The description adds no meaning about the symbol beyond what the schema already states. Baseline 3 applies when schema coverage is this high.

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 names a specific resource and scope: the process stage of an industry value chain a given stock occupies, plus listed competitors at that same stage, illustrated with a semiconductor back-end/packaging example. An agent can tell this apart from get_value_chain_map and list_value_chains by the fact that it is scoped to one stock. It stops short of explicitly naming those siblings as alternatives.

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?

Usage is only implied: the phrasing '이 종목이' signals it takes a single stock, and the example suggests it is for classifying a company within a chain. There is no explicit statement of when to prefer this over get_value_chain_map or list_value_chains, and no prerequisites or exclusions are given.

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