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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safety profile is covered. The description adds the concept of harnesses as persistent context memories, which is useful context. However, it doesn't disclose default ordering, pagination behavior, or what happens when no harnesses exist. With annotations covering safety, a 3 is appropriate.

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?

Two sentences with zero waste. The first sentence states the action and scope, the second defines the resource type. The wallet_address auth note is in the schema where it belongs. Every sentence earns its place.

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?

Complete for a read-only list tool with 100% schema coverage and annotations covering safety. The only minor gap is not describing return format or pagination, but for a simple list tool with no output schema, the description plus schema is sufficient. The sibling list shows search_harnesses exists, so an agent might wonder when to use which, but the description's definition of harnesses helps.

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%, so the schema already documents all three parameters. The description adds the wallet-address scoping context ('Owner scope. Over the public MCP door this is derived from your auth token') which is helpful, but doesn't add meaning beyond what the schema provides. Baseline 3 is correct.

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 ('List') and resource ('harnesses for a wallet address'), and defines what harnesses are (persistent context memories: personas, preferences, strategies, knowledge, compliance). This clearly distinguishes it from siblings like get_harness, search_harnesses, create_harness, and delete_harness.

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 this is the listing tool for harnesses scoped to a wallet address, and the schema notes the wallet_address is derived from auth token over the public MCP door. It doesn't explicitly name alternatives like search_harnesses or get_harness, but the context is clear enough for an agent to select it for listing all harnesses.

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