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

The annotations already declare destructiveHint=true and idempotentHint=false, so 'Destructive; no undo' largely restates what structured data conveys. It adds emphasis but omits genuinely useful behavior: whether deleting a nonexistent key errors or silently succeeds (relevant given idempotentHint=false), and whether the arena key must match the entry owner.

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?

Front-loaded with the WHEN clause and a concrete example in a single compact line — no filler. Minor waste in leading with the tool name, which repeats the title/name field verbatim.

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 and annotations carry the safety profile, so the description needn't explain return values or risk. What remains is a destructive, non-idempotent mutation, and the explicit 'no undo' plus example cover the essentials for correct invocation.

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% and both parameters are documented, so the schema does the heavy lifting. The inline example fixes the invocation shape for mkey, but the description says nothing about the 'key' auth parameter or mkey syntax beyond the placeholder. Baseline 3 applies.

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+resource: delete a memory key. That cleanly separates it from the read siblings (memory_get, memory_list, memory_search) and the write sibling (memory_put). It's clear but doesn't explicitly name memory_put as the overwrite alternative, which is the one ambiguity.

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?

'WHEN: delete one of your memory keys' gives an explicit trigger, which is more than most. However, there's no when-NOT guidance and no acknowledgement that memory_put can overwrite a value without destroying it — an agent weighing delete vs. overwrite gets no routing help.

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