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 without description help. The word 'available' hints at scoping (only usable plugins), but the description says nothing about pagination, filtering, or what 'available' excludes — a small but real gap given no output schema.

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 short sentence with the resource named up front and zero filler. Nothing is buried or redundant.

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?

For a zero-parameter read-only list tool this is close to adequate, but with no output schema the description should hint at what each plugin entry contains (identifier, name, enabled state) so the agent knows what it can do with the result. Without that, the agent must discover the return shape empirically.

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 tool takes no parameters, so there is no parameter semantics to explain and the baseline of 4 applies. The description correctly avoids inventing filtering options that the empty schema does not support.

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 states a specific verb and resource ('List available connector plugins'), which makes the operation immediately identifiable. It does not differentiate itself from the similarly named connector_discover or connector_status siblings, leaving the agent to infer the distinction from names alone.

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?

Usage is only implied: an agent would reasonably call this to enumerate plugins before invoking connector_enable or connector_run. There is no explicit statement of when to use this versus connector_discover or connector_status, and no prerequisites or exclusions are given.

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