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

Annotations already declare readOnlyHint=false and idempotentHint=true, so the mutation/idempotency profile is covered. The description adds non-obvious behavior beyond that: the personal-key-only auth constraint and the fact that this targets the manual list (leaving directory-synced members alone). It does not explain what the response contains or how refusals surface, but the auth caveat is real value.

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 sentences, zero padding, with the core action front-loaded and the auth caveat second. Every clause earns its place.

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 full annotation coverage, a fully described schema, and no output schema, the description covers the key operational constraint an agent needs (key type). It leaves the refusal/force interaction to the schema, which documents it well, so the gap is minor.

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%, and the schema already explains team_id provenance (list_teams), the replace-not-merge semantics of membership_ids, and the force/escalation-policy behavior. The description adds nothing about parameters, 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 and resource ('Replace a team's manual member list') and qualifies it with 'manual', which separates it from directory-synced memberships and from single-member siblings like update_member/remove_member. An agent can tell at a glance that this is a bulk overwrite of the team's manually managed roster.

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?

It gives a hard prerequisite ('Requires a personal API key; organization keys cannot manage teams'), which is genuinely useful routing information, but it never names an alternative tool or the condition under which an agent should prefer update_member/remove_member over this bulk replace. Usage is implied rather than stated.

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