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

Annotations only flag destructiveHint=true; the description adds real value by disclosing the client-visibility consequence and the two-phase confirmation behavior, which prevents an agent from thinking a no-confirm call actually deleted anything. It stops short of saying whether the deletion is hard or reversible, or what happens to already-assigned clients.

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?

One compact sentence plus a parenthetical that front-loads the operation, then the side effect, then the safety gate. Nothing is wasted and no clause needs a second read.

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 2-parameter destructive tool with no output schema, the definition covers purpose, effect on clients, and the preview/execute gate, which is enough to call it correctly. Only the reversibility/soft-delete question and id provenance remain open.

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 50%: `confirm` is fully documented in the schema, while `id` has no description at all. The description reinforces the confirm gate's semantics but does not clarify what `id` refers to (library item id vs document id) or where to obtain it, leaving the undocumented half unaddressed.

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?

Specific verb ("Remove") plus resource ("a document from the coach's library") plus the client-facing consequence, which cleanly separates it from create_library_item, update_library_item, and list_library_items. An agent can tell what this does 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?

Removal usage is implied clearly by "Remove", and the confirm gate is spelled out, but there is no explicit routing guidance (e.g., use update_library_item to hide/edit instead, or list_library_items to find the id first). No when-not conditions are given.

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