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

Annotations already declare readOnlyHint=true and openWorldHint=false, so the safety profile is covered. The description adds meaningful context beyond that: the ordering (newest first), the detection semantics (changed after first observed = possible rug pull), a push alternative, and cost ('Free'). It does not address limit/pagination behavior, keeping it below 5.

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?

Three short sentences, front-loaded with the core identity and ordering, followed by the subscription path and cost. No sentence is filler; 'Free' is a legitimate invocation-affecting detail.

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-value explanation is unnecessary, and annotations cover the safety profile. The description tells the agent what the feed contains and how to get it live. The remaining gap is explicit differentiation from the other scan_* siblings and the limit semantics.

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% and the description never mentions the 'limit' parameter. However, the schema itself supplies the default (25), min (1), and max (100), and the parameter name is self-evident, so the agent can invoke correctly without description help. The description fails to compensate for the coverage gap, capping this at minimum-viable.

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 resource and scope: MCP servers whose tool definitions changed after first observation (rug-pull detection), ordered newest first. An agent can distinguish this from scan_search or scan_server by the 'changed after first observed' framing. It does not explicitly name a sibling, 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 usage by pointing to the Live channel 'scan' subscription as an alternative push mechanism, which is useful routing context. However, it gives no explicit when-to-use guidance versus scan_search, scan_rescan, or scan_watchlist, leaving the agent to infer which scan tool to pick.

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