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

Annotations already declare destructiveHint=true, idempotentHint=true and readOnlyHint=false, so the safety profile is covered. The description adds genuine value beyond them: the 403 not_note_author and 403 system_note_read_only conditions tell the agent that only authored notes can be deleted and system notes are protected.

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 short lines with no wasted words; the core action is front-loaded. The 'Same rules as editing' clause is terse and slightly cryptic, requiring knowledge of the update tool's docs, but it is not padding.

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?

Adequate for a three-required-param delete with full annotations and full schema coverage, and it does disclose the key authorization failure modes. It stops short of confirming whether the deletion is permanent/hard vs soft or what a successful response contains.

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 all three UUID parameters and their error semantics (404 agent_not_found, 403 agent_not_authorized, 404 not_found) are already documented in the schema. The description adds no parameter-level detail, so the 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?

States a specific verb (delete) and resource (note). The name delete_contact_note and the sibling set (create_contact_note, update_contact_note, list_contact_notes) make the target unambiguous. It does not, however, explicitly distinguish itself from those siblings in prose.

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?

There is no when-to-use vs alternative guidance and no prerequisites stated. The 'Same rules as editing' cross-reference is about error behavior, not about when to pick this tool over update_contact_note or the other delete_* siblings.

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