daily_summary

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

With no annotations, the description carries the full burden, and it does disclose the key behaviors: it returns all entries for a day and falls back to today when the date is omitted. It does not state that the operation is read-only, how results are ordered, whether entries of all types are included, or anything about response size, leaving meaningful gaps.

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?

Two short clauses, zero filler, with the resource scope stated first and the default behavior second. Nothing could be removed without losing 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 one-parameter read tool this is close, but there is no output schema, so the description is the only source describing the return value, and "everything logged" is vague about shape, ordering, and whether it includes all entry types. A sentence on what comes back would make it complete.

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?

The single parameter has no schema description, so the description must compensate, and it does: it names the date parameter's expected YYYY-MM-DD form and reveals the default behavior (today) that appears nowhere in the schema. Only the default's effect on edge cases (e.g. timezone) is left unexplained.

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?

"Everything logged on a given date" clearly identifies the resource (log entries) and the scope (one calendar day), so an agent can tell this is a per-day retrieval tool. It does not, however, contrast itself with siblings like search_diary or stats, which is the only thing keeping it from 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?

"Defaults to today" hints at the common no-argument case, but there is no explicit when-to-use guidance and no mention of when to prefer search_diary or stats instead. The agent must infer the distinction from tool names alone.

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