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), and the description adds genuinely new context: descending order, an explicit auth requirement (valid Key required, anonymous disabled), and the per-event source field (mcp/page/server) plus payload shapes for action_call and push. This goes beyond what the annotations provide.

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?

Dense but well-front-loaded: purpose first, then parameters, then return-shape and auth details. Every clause carries information (enum values, bounds, payload fields) with little waste, though the single run-on paragraph is heavy.

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 must carry return-value context and does so reasonably: it explains the descending ordering, the source attribution field, and the payload contents for action_call and push. Auth and required params are covered, leaving only minor gaps like pagination and date format.

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%, so the description carries the full burden and largely does: slug is marked required, type/from-to/limit are listed, limit's bound (≤500) is stated, and the type enum values are enumerated. The only gap is the format of from/to (string timestamps), which is left unspecified.

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 with scope: pull events by type across sessions in descending order, and enumerates the type values (chat_user / chat_assistant / track / action_call / page_open / push). The cross-session scope implicitly distinguishes it from get_session_log, but no sibling is named explicitly, so it falls 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?

The description implies its use case by highlighting the billing/troubleshooting evidence chain in action_call payloads, which hints at diagnostic usage. However, it never states when to pick this over get_session_log, list_actions, or get_stats, leaving the routing to inference.

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