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

The description states that setting mark_read:true flags events as read, which modifies state (mutates the feed), but annotations declare readOnlyHint=true, indicating no state modification. This contradiction is harmful; score 1 per rules.

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 front-loaded with the primary purpose, each sentence adds specific information (return structure, filtering options, mark_read behavior, alternative access). It is relatively concise at 5 sentences with no redundancy.

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?

The description covers the return fields, filtering, and mark_read behavior. Despite the lack of an output schema, it gives enough context for an agent to understand the return structure. The only minor gap is no mention of the 'limit' parameter, but it's in the schema.

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 100%, so baseline is 3. The description adds useful context for 'since' (ISO timestamp) and 'mark_read' (explains effect on subsequent calls), but does not mention 'limit' or 'unread_only', which are already well-described in the schema. Overall, it adds moderate value 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 starts with 'Pull fired events from your subscription feed' which is a specific verb (pull) and resource (fired events from subscription feed). It clearly distinguishes from sibling tools like list_subscriptions (which lists subscriptions) by focusing on events from the feed.

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 explains how to filter by type and since, and how to use mark_read for read tracking. It mentions that polling works and provides an alternative endpoint for scripts, giving good context on when and how to use the tool, though it does not explicitly exclude alternatives.

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