diary_get

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

Annotations already declare readOnlyHint=true and openWorldHint=false, so the safety profile is covered. The description adds real context beyond that: entries are impressions rather than verified facts, and rolled-up dates silently fall back to weekly_log, which is a non-obvious behavioral trait. It stops short of describing output shape or pagination.

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?

Five short clauses, none of which waste words, and the core semantics (recent default, weekly label) are front-loaded. The telegraphic style is dense but readable and earns its length.

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 tool with no output schema and a fully documented 3-param schema, the description supplies the missing domain framing (what a diary entry is, its reliability) and the date/week fallback rule. Return format is undescribed, but no output schema exists, so the remaining gap is minor.

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 baseline is 3, but the description adds meaning beyond the schema by explaining how date and week interact (the weekly_log fallback for rolled-up dates) and when to omit each. That is genuine semantics the schema does not carry.

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+resource ('Read daily_log diary entries') and characterises the content ('impressions, not verified facts'), which separates it from the memory_* siblings that return authoritative memories. It does not explicitly name a sibling alternative, so it stops short of 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?

Gives concrete selection guidance: omit date for today+yesterday, use week for weekly_log, and dates rolled up into weekly_log fall back there. 'Fetch explicitly when needed; do not treat diary as ground truth' sets a usage posture. It lacks explicit when-not/alternative routing to the memory_* tools.

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