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

Annotations declare destructiveHint=true and idempotentHint=true but say nothing about mechanism. The description adds the crucial nuance that an empty string clears a field, which is exactly the behavior an agent needs to avoid accidental data loss, plus the fact that omitted fields are preserved.

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 tight sentences with no filler. The field list comes first and the critical partial-update rule is front-loaded in the second sentence.

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 mutation tool with no output schema, the description covers purpose, field semantics, and the destructive edge case. Remaining gaps (e.g., what the response contains, whether simultaneous multi-field updates are allowed) are minor given annotations carry the safety profile.

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 0%, so the description carries the load: it maps the three parameters to their meaning and, more importantly, explains the omit-to-keep / empty-string-to-clear semantics that the schema does not encode at all. Length limits are repeated from the schema but the semantic layer is genuinely additive.

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 names a specific verb (changes) and the exact resource fields (display name, bio, location), making it unambiguous against siblings like update_link or add_link. It also scopes each field with a length limit, reinforcing what the tool operates on.

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 explicit when-to-use vs. alternative guidance and no sibling tool is named. Usage is only implied, though the partial-update rule (omit to keep, empty string to clear) does tell the agent how to invoke it correctly.

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