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

Even with readOnlyHint=true and destructiveHint=false annotations, the description adds meaningful behavioral disclosure: returns CSV with exact column order, defaults to latest quarter, ignores instrument suffixes, and returns JSON candidates on ambiguous symbols. This goes well beyond the annotations and enriches the agent's mental model.

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?

Three dense sentences carry the full purpose, return format, parameter semantics, default behavior, and ambiguous-symbol handling without redundancy. Front-loaded with the primary purpose and free of fluff.

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?

With no output schema, the description fully covers the return format (CSV columns), the parameter combinations, the default behavior, and the ambiguity fallback. Nothing an agent needs to call and interpret this tool is missing.

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 description coverage is 100%, so baseline is 3. The description enhances this by framing all=true as useful for spotting ownership changes and quarter as a historical snapshot, and by reinforcing the entity-level suffix behavior. This is additional practical meaning beyond the schema's already-solid parameter docs.

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 ('Get') and resource ('top-20 ranked shareholder list for a CSE company'), which clearly identifies the data being returned. It also states the entity-level nature and references the sibling get_financial_statement, distinguishing this tool from others in the family by the unique shareholder-list resource.

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?

Gives clear parameter usage context: default latest quarter, all=true for all quarters, quarter for a specific snapshot, and the precedence of quarter over all. It does not explicitly list when-not-to-use scenarios or alternative sibling tools for shareholder data, but the tool's unique purpose makes the usage context clear.

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