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

Annotations already declare readOnly/idempotent/no-destructive, so the bar is lower, and the description adds real value: it discloses the "workspaces:read" scope requirement and the implementation caveat that no single-workspace GET exists so it filters the user's workspaces list. That caveat explains result semantics an agent would otherwise misread.

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?

The core action and scope requirement bookend the description efficiently. The stacked parenthetical about workspace keys is slightly hard to parse but does not waste sentences.

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 wisely tells the agent the return value is the matching entry from the workspaces list (so shape matches list_workspaces). Auth scope, selection semantics, and the sibling-driven discovery path are all covered; only an explicit pointer to hub_get_default_workspace is missing.

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 100%, so both account and workspace are fully documented in the input schema, including override and multi-account failure behavior. The description adds no syntax or selection detail beyond what the schema already provides, so 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+resource ("Get details for the selected workspace") and scopes it to either the selected workspace or the key-bound workspace. The note that it returns the matching entry from the user's workspaces list effectively distinguishes it from list_workspaces, though it never names a sibling directly.

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?

Implies when to use it (you want details on the current/selected workspace) but gives no explicit when-not guidance or routing to hub_get_default_workspace or list_workspaces. The useful discovery hint ("discover candidates with list_workspaces") lives only in the parameter schema, not the description.

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