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

Annotations already declare destructiveHint=false and openWorldHint=false, so the safety profile is partly covered. Beyond that, the description adds nothing: it does not say whether unspecified fields are preserved, what happens when contact_id is invalid, or whether the update is partial or full. For a mutation tool that returns no output schema, that silence is a real gap.

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 front-loaded sentence with zero filler or redundancy. It is efficient, though the brevity reflects under-specification rather than disciplined information design.

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?

This is a five-parameter mutation with no output schema, and the description covers only the bare action. It omits partial-update semantics, failure behavior for a missing contact, and any routing relative to desk_create_contact or desk_merge_contacts, leaving an agent to guess at important behavior.

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 every parameter (contact_id, name, notes, organization, purpose) is already documented in the schema with types and constraints. The description adds no additional meaning about which fields are updatable or how they interact, but the schema does the heavy lifting, making 3 the appropriate baseline.

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: 'Updates an existing SautiDesk customer contact.' An agent can tell it is a mutation on a contact record. However, it does nothing to distinguish itself from sibling tools like desk_create_contact, desk_lookup_contact, or desk_merge_contacts, which all operate on the same resource.

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 guidance, no prerequisites, and no mention of alternatives. The word 'existing' faintly implies the contact must already exist (so use desk_create_contact otherwise), but that inference is left entirely to the agent. No exclusions or routing hints are given despite several contact-related siblings.

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