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

The description discloses important behaviors: the mark_read parameter modifies state by flagging events as read. However, annotations indicate readOnlyHint=true, which contradicts this side-effect. The description is transparent about the mutation, but the contradiction with annotations is notable.

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?

The description is concise and front-loaded, starting with the core purpose. Every sentence provides useful information without redundancy. It efficiently covers return values, filtering, mark_read behavior, and an alternative access method.

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?

Given the absence of an output schema, the description adequately explains return values (source, citation_uri, raw payload) and parameter effects. It covers all key aspects: filtering, pagination (limit), reading state management, and alternative access. The information is sufficient for an agent to use the tool correctly.

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 input schema already describes all 5 parameters (100% coverage). The description adds value by explaining the purpose of each parameter (e.g., 'Filter by type', 'ISO timestamp', 'mark_read:true to flag returned events read') and details about the return fields, providing context beyond the schema.

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?

The description clearly states the tool's purpose: 'Pull fired events from your subscription feed.' It specifies what is returned (source, citation_uri, raw event payload) and mentions filtering options. This distinguishes it from sibling tools like 'list_subscriptions' which manage subscriptions rather than retrieve events.

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 provides guidance on when to use the tool (polling works fine) and mentions an alternative (the same feed at a REST endpoint for scripts and dashboards). It explains the mark_read flag for managing read state but does not explicitly state when not to use this tool versus siblings.

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