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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety and open-world profile is covered. The description adds the scope (all collections, not one), but says nothing about freshness, rate limits, or pagination behavior beyond what the schema documents.

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?

A single sentence, front-loaded with the resource and immediately qualified by scope. Nothing is wasted and there is no burying of key information.

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?

An output schema exists, so return values need not be explained, and annotations cover the safety profile. However, for a three-parameter paginated feed with event-type filtering, the description gives no operational guidance on iterating cursors or narrowing event types, leaving a small but real gap.

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 100% and all three parameters (limit, cursor, event_types) are documented in the schema, so the schema does the heavy lifting. The description contributes no additional parameter semantics, which is the expected 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?

Names a specific resource (OpenSea activity feed) and scopes it precisely as 'marketplace-wide ... across every collection', which is the key distinction from the sibling activity tools. It does not name those siblings (opensea_collection_activity, opensea_item_activity, opensea_profile_activity) explicitly, but the scope phrase effectively separates it.

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 'marketplace-wide' phrasing implies when to reach for this rather than a collection- or item-scoped feed, but there is no explicit when-to-use statement, no named alternatives, and no note about event_types filtering or pagination workflow.

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