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

Annotations already cover read-only, idempotent, and non-destructive nature, and the description adds context by specifying the source (full-year and half-year announcements) and the inclusion of management guidance, which is not apparent from annotations. No contradictions.

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 two sentences with no fluff wants. It front-loads the primary resource and then lists included metrics, which is efficient and structured for quick scanning.

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?

Given the tool's moderate complexity, full schema coverage, and an output schema that likely defines return structure, the description is sufficient. It provides essential behavioral context (source, included metrics) without over-explaining. No critical gaps.

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 coverage is 100%, so the schema already documents all parameters. The description does not add extra meaning beyond the schema; it merely implies the tool uses ticker and filters. Baseline 3 is appropriate.

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 verb ('Get') and resource ('earnings results for an NZX company'), and lists key fields included (revenue, net profit, etc.). It differentiates clearly from siblings such as get_financials and get_dividends, but does not explicitly name or differentiate against a specific sibling tool beyond the general 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?

The description implies usage by indicating it is for earnings results from announcements, but it does not explicitly state when to use this tool versus alternatives like get_financials or get_metrics. No exclusions or conditions are given.

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