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

Annotations only declare readOnlyHint=false (a mutation), so the description adds real value: partial-update semantics, the requirement to translate colloquial zones into IANA names yourself, and the instruction to confirm what was set. It does not cover auth requirements or error behavior, but the mutation-safety context is well conveyed.

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 action, then constraints, then examples, then the alternative tool. Every sentence carries a distinct instruction, though the timezone example parenthetical makes it slightly denser than necessary.

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 7-param, zero-required mutation with no output schema, the description covers scope, partial updates, input normalization, and post-call confirmation. It is close to complete; only failure/permission behavior is unaddressed.

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 only 43%, but the description names nearly every parameter's field and supplies the most important semantic rule the schema lacks: accepted timezone inputs and their IANA mappings. It compensates well above the low-coverage baseline, though first/last name and URL formats remain schema-only.

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 and resource (update the user's own profile) and enumerates exactly which fields are in scope: timezone, name, headline, company website, LinkedIn URL, X handle. It further disambiguates from the sibling update_profile_fields by routing 'other facts about them' there.

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 an explicit trigger ('when they ask'), an operational constraint ('Only pass the fields they asked to change'), and names the alternative tool for out-of-scope facts. Nothing about when-to-use is left to inference.

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