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

Annotations already declare destructiveHint=true and idempotentHint=true, but the description goes well beyond them: it explains the safe dry-run default, discloses the pinned-entry exception, enforces a filter precondition, and states the owner-only auth requirement (handle + secret). This is rich behavioral context an agent needs before invoking a destructive tool.

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?

Five short, front-loaded sentences with no filler; purpose leads, then safety, exception, precondition, and auth. Every sentence carries a distinct, actionable fact.

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 destructive, no-output-schema tool, it covers safety, prerequisites, the pinned exception, and auth. It stops short of describing the response shape after a real deletion (only the dry-run return is mentioned), 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 covers ~67% of parameters; the description adds meaning for dry_run (safe default, returns candidates) and compensates for the undocumented handle/secret by stating they are the owner credential. The filter parameters (older_than_days, not_read_in_days) are only implied by 'matching filters' rather than explained, so it stops short of full coverage.

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 verb+resource ('Delete memory entries matching filters') that clearly separates it from the store/recall/search/list memory siblings by its destructive intent. The 'matching filters' scope and the pinned/filter constraints make the operation unambiguous without opening the schema.

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?

Gives concrete operating context: dry_run=true default is safe, at least one filter is required, and pinned entries are exempt. It does not name alternative tools (e.g., list_memory or search_memory) for the non-deleting case, so the routing guidance is implicit rather than explicit.

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