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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive, closed-world), so the bar is lower. The description still adds real value beyond them: 'Missing metrics are unknown, not zero' clarifies data semantics and 'does not trigger paid refreshes' discloses a cost side-effect neither annotations nor schema mention.

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?

Three tight sentences, each earning its place: the core action, the data-semantics caveat, and the sibling routing. Front-loaded with the main verb and no 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?

An output schema exists, so return values need not be described, and annotations cover safety. However, with 0% parameter documentation and a listed sibling (get_analytics_summary) left unaddressed, the definition is not fully complete for correct invocation.

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 0% across three parameters (brandId, limit, cursor), so the description carries the full burden of explaining them. It says nothing about pagination via limit/cursor or the brandId identity requirement, leaving an agent to infer input behavior entirely from bare JSON types.

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 stored content metrics') and adds a scope qualifier ('stored', 'captured_at timestamps') that separates it from live/fresh data. It does not, however, distinguish itself from the very close sibling get_analytics_summary, leaving one likely confusion unresolved.

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?

Explicitly routes the agent to alternatives: get_report_capabilities and get_channel_report for saved X/channel reports, and request_channel_report for fresh reports, which is a strong when-to-use signal. It stops short of a 5 because it never contrasts with the closest sibling, get_analytics_summary.

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