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

Annotations already cover readOnly/idempotent/openWorld, so the bar is lower, and the description adds genuine context: it distinguishes derived_access (from platform roles) vs granted_access (human-granted in Subo) and states no mutation is possible here. It does not discuss return format, which is left unaddressed.

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?

Three focused sentences: purpose first, then field disambiguation, then scope boundary. Every sentence carries information, though the two backticked field names make the middle sentence slightly dense.

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?

With no output schema, the description carries the return-value burden and does a fair job naming XP, accomplishments, and the two access fields. It is complete enough to call correctly, though it doesn't hint at shape or structure of the returned member.

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 single member_id param is documented with its source ('from list_members'). The description adds no parameter-level detail beyond the schema, so the baseline of 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 ('Get one member') and names what it returns (XP, accomplishments, access). The singular 'one member' implicitly distinguishes it from the sibling list_members, so an agent can route correctly without opening the schema.

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?

Clearly scoped to reading a single member and explicitly rules out mutation ('Changing either is not available here'), routing the agent elsewhere for edits. It does not name the alternative tools (e.g. modify_xp, modify_accomplishments), so it stops short of explicit alternatives.

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