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

Annotations already declare read-only, non-destructive, closed-world, so the safety profile is covered. The description adds real value beyond that: required permission scopes and the fact that bot-score/decision dimensions depend on Bot Management, which is exactly the kind of failure-mode context an agent needs. It does not mention aggregation windows, sampling, or result-size behavior.

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: what it aggregates and by what, then permissions, then sibling relationship. Front-loaded with the core capability and no redundant restatement of the title.

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 15-parameter aggregation tool with an output schema, the description covers purpose, auth prerequisites, and the key alternative. Gaps remain around filter interaction (bot_score_min/max pairing with bot_score_bucket), time-range defaults, and path_preset usage, but these are partially mitigated by schema descriptions.

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 47% across 15 parameters, so the description needs to compensate and largely does not. It enumerates the group_by values (which the enum already provides) but says nothing about limit, methods, hostname, path_prefix, bot_score_min/max, or how filters combine, leaving roughly half the parameters undocumented in both places.

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 ('Aggregate') and resource ('eyeball HTTP requests') plus the exact set of grouping dimensions, which matches the group_by enum. It also names the sibling it is not (cf_firewall_events, WAF-only), so an agent can distinguish the two without opening schemas.

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 clear preconditions to use it (Zone Analytics Read; Bot Management for bot dimensions) and frames its role relative to cf_firewall_events. It does not, however, distinguish itself from the adjacent cf_http_security_samples or cf_http_security_top_talkers siblings, leaving that inference to the agent.

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