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

The description describes setting mark_read:true to flag events as read, which implies a state change. However, the annotations declare readOnlyHint:true and destructiveHint:false, creating a contradiction. According to guidelines, this yields a score of 1.

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 four well-structured sentences. The first sentence states the purpose, followed by return fields, filtering options, and special behavior. Every sentence adds essential information without redundancy or verbosity.

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 tool's five optional parameters, no output schema, and use case (polling for alerts), the description covers all key aspects: purpose, return fields, filtering, mark_read effect, and an alternative access endpoint. It lacks explicit mention of pagination or error handling but is sufficiently complete for this context.

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 value by specifying return fields (source, citation_uri, raw event payload), giving an example filter value ('sec_8k'), clarifying that 'since' expects an ISO timestamp, and explaining the effect of 'mark_read'. This exceeds baseline.

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 uses specific verbs ('Pull fired events from your subscription feed') and clearly states the resource (recent alerts) and the action. It distinguishes this tool from siblings like 'list_subscriptions' by focusing on 'recent alerts' specific to subscription feed 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 clear usage context: it's for pulling the most recent alerts from a subscription feed, with optional filtering by type and since timestamp. It mentions mark_read behavior and confirms polling works. However, it does not explicitly state when not to use it or name alternatives among siblings.

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