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

Annotations already declare readOnly/idempotent/non-destructive/closed-world, so the safety profile is covered. The description adds a genuine constraint not present in the schema: a hard 92-day cap, plus confirmation that results are scoped to the signed-in user. It does not say how days with no entries are represented, which is the main remaining gap.

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?

One sentence, front-loaded with the returned data, then the range limit, then the ownership scope. Nothing is redundant and every clause carries information.

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 read-only, three-parameter aggregation tool with no output schema, the description covers what is returned, the range cap, and the data owner. Missing only edge-case behavior such as zero-entry days or how the tz parameter shifts day boundaries.

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 only 33% – startDate and endDate have patterns but no descriptions, and only tz is documented. The description compensates partially by constraining the range ('max 92 days'), which applies to the date parameters and is not expressible in the schema, but format and inclusive/exclusive boundary semantics remain undocumented.

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 plus the exact payload ('Per-day macro totals and entry counts') and the scope ('signed-in user's Joiva log'). It implicitly separates itself from joiva_get_day by specifying a range, though it never names the sibling 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?

The phrase 'for a date range' implies this is the multi-day counterpart to joiva_get_day, but no alternative tool is named and no when/when-not condition is stated. The agent must infer the routing decision from the range semantics alone.

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