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

Annotations already declare non-destructive, idempotent, non-read-only behavior, so the floor is set. The description adds the valuable exclusion set (email/role/balance/payout are immutable here), but says nothing about partial-update semantics — whether omitted fields stay untouched and whether arrays like topics or languages are replaced or merged.

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 sentences, zero filler, with the scope constraint front-loaded before the exclusions. Nothing here repeats the schema or wastes tokens.

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 nine-parameter mutation with no output schema and no per-parameter documentation, the description should at minimum state that all fields are optional and how omission/array replacement behaves. It covers only exclusions, leaving the actual update contract under-specified.

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% — all nine properties carry only types and maxLengths, with no descriptions. The tool description compensates only by naming the fields that are excluded; it never lists or explains the editable fields (bio, title, topics, industry, names, photoURL, languages, categories), so the agent learns the contract only from property names.

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?

"Updates your own public profile fields" gives a specific verb (update), resource (profile), and scope (your own, public fields), which cleanly separates it from admin-style or read tools. It does not name the read counterpart get_my_profile, so differentiation is implicit rather than explicit.

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?

The sentence "Email, role, balance, and payout data cannot be changed here" usefully tells the agent when NOT to use it, but never names the alternative tools (add_payout_method, update_rate, etc.) that would handle those fields. The agent must infer routing from the sibling list rather than being directed.

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