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

Annotations already declare readOnly, idempotent, non-destructive, and closed-world, so the safety profile is covered. The description adds value by disclosing the briefing's actual contents (participants, status, decisions, open questions, next step) and, notably, that the delta is 'caller-specific' and relative to last look — context an agent cannot derive from the annotations.

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 tight sentences with the core purpose front-loaded and the content enumeration second. No filler, though the long comma-separated list slightly blurs into the delta clause.

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, the description correctly carries the burden of describing the return shape by enumerating the briefing's sections. Combined with access rules and the caller-specific delta note, it is sufficiently complete for a read-only summarization tool, though focus-value behavior remains unstated.

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% and the description lists content categories (next step, decisions, open questions, delta) that map onto the focus enum values, partially compensating for the low coverage. But it never explains the focus enum itself or the difference between 'full' and the narrower focuses, leaving the parameter only loosely clarified.

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?

Specifies a clear verb (summarize/generate a briefing) and resource (coordination thread), and the word 'briefing' implicitly contrasts with fetching a raw thread via get_coordination_thread. However, it never names the sibling alternatives (get_coordination_thread, list_my_coordination_threads) explicitly, so the differentiation is inferred rather than stated.

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?

It states visibility/access conditions ('visible to the household member or an active participant/watcher') and notes that professional callers are limited to threads where they participate, but gives no explicit when-to-use-this-vs-get_coordination_thread guidance. Usage is implied by the noun 'briefing' rather than spelled out.

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