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

Beyond the annotations (readOnly/idempotent/openWorld), it discloses the noisy-ness of the raw feed and why defaults filter, the truncation behavior when limit is large ('cut to the events nearest now... the result says how many were left out'), and the exact composition of the vsEstimate delta field including that the label is direction-only. These are non-obvious behaviors an agent needs.

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 purpose sentence followed by a rationale, a special-case instruction, and an organized Args block; the Returns line prevents the reader from guessing. It is somewhat long and the countries/impact text partially duplicates the schema descriptions, which is minor waste but not filler.

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 and 7 undocumented-in-schema parameters, the description still supplies both the parameters and the return shape ({ totalMatched, returned, filters, economicCalendar }) plus the nested vsEstimate semantics. Nothing needed to call or interpret the 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 only 29%, so the description carries the burden and does so fully: it documents all seven parameters with defaults, the fromDate/toDate-vs-daysBack/daysForward alternatives, valid enum-ish values for impact ('High','Medium','Low'), common country values, and the empty-string convention for disabling filters.

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 and resource ('Returns upcoming and recent economic events') and grounds it with concrete examples (Fed meetings, jobs reports, CPI, GDP). This clearly separates it from company-specific siblings like get_earnings_calendar and get_ipo_calendar, though it never names those siblings explicitly.

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 real when-to-use guidance: the default filtering exists 'because the raw feed includes hundreds of low-impact items from every country,' and it explains setting daysBack to 35 to retrieve released actuals. It also explains how to opt out of each default filter. It lacks any explicit when-not-to-use or alternative-tool routing.

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