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

The annotation readOnlyHint: true already covers the safety profile, so the bar is lower. The description adds only the 'upcoming' scope, which is implicit in the tool name. It doesn't disclose any additional behavior like pagination, output format, or handling of missing symbols. It's consistent with annotations but adds minimal value beyond them.

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 a single sentence with zero waste, front-loaded with the core purpose. It's appropriately concise for a simple read-only tool. However, it's so brief that it misses any usage nuance, which slightly detracts from optimal structure.

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 schema fully covers parameters and the readOnlyHint annotation is present, the description is minimally adequate. However, it doesn't describe the return shape (e.g., list of dates/symbols) or the default behavior (all holdings/watchlist) which is only in the schema. For a tool with no output schema and three optional params, a bit more context would improve completeness, but the schema compensates.

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% – all three parameters (symbols, daysAhead, includePast) have detailed descriptions in the schema. The description adds no parameter-specific meaning, so the baseline 3 applies. No extra syntax or context is provided beyond what the schema already states.

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 states the tool provides a calendar of upcoming periodic reports, which is a clear verb+resource. It distinguishes it from siblings like get_earnings_deepdive (which implies deeper analysis) and get_report_event (singular event). However, it could be more specific about filtering or scope, so it doesn't earn a 5.

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 gives no guidance on when to use this tool vs. alternatives. With many sibling tools like get_earnings_deepdive, get_report_event, and get_dividends, the agent gets no differentiation or context on selecting this one. No exclusions or conditions are provided.

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