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

Annotations already declare destructiveHint=true and readOnlyHint=false, so the safety profile is covered. The description adds real value beyond that by disclosing the conditional semantics: hard delete (including the associated card) when there is no answer history, versus a soft 'don't learn' mark when history exists. It still does not say whether the delete is reversible or what the caller gets back.

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 sentence, verb-first, with the two behavioral branches cleanly split after the colon. No filler or repetition; a touch more structure (e.g. stating the input) would be needed for a 5.

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 single-parameter mutation with no output schema, the description covers the important behavioral fork but omits what the call returns, what happens on an invalid or already-removed id, and whether the deck/card structure outside the entry is affected. Annotations carry the destructive signal, so the omission is a gap rather than a failure.

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% and the single parameter (lexicon_id, integer) is never mentioned in the description. The name is self-explanatory, so an agent can likely supply it, but the description does not compensate for the documentation gap as the low-coverage rule requires.

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?

The description names a specific verb (remove) and resource (vocabulary entry) and then spells out the two distinct outcomes, which separates it from siblings like vocab_add, mark_known, and quiz_delete. It does not explicitly name an alternative tool, so it stops short of the top mark.

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?

Usage is only implied: the agent learns what happens in each state, not when to choose this tool over mark_known or quiz_delete. There is no statement of prerequisites, irreversibility tradeoffs, or the alternative path for entries with history.

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