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

Annotations already declare readOnly, idempotent, openWorld and non-destructive, so the safety profile is covered. The description adds genuine value by disclosing what is withheld ('public prose, aliases, external links and media are withheld') and that identity is not established. But 'bounded direct-record admission without recursive content certification' is opaque jargon that conveys little actionable behavior.

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 purpose is front-loaded in the first sentence, which is good. The following four sentences are terse but several are cryptic enough ('identity evidence and uncertainty remain separate') that they consume space without yielding clear meaning.

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?

There is no output schema, so the description should characterize the returned record; instead it only says 'compact' and lists omissions. Combined with three undocumented parameters and no return-shape detail, an agent lacks enough to call this reliably.

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%, so the description carries the full burden for 4 parameters. It only addresses 'qids' (and the 10-item cap, which the schema already encodes via maxItems); lang, fields, and refresh are left entirely unexplained in both schema and prose.

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 first sentence states a specific verb and resource: 'Compact selected Wikidata facts for at most 10 supplied QIDs', which an agent can act on. It also partially differentiates from siblings by stating 'Fact lookup does not establish local identity', implicitly contrasting with kg_audit_identity/kg_discover_identity/kg_resolve. The heavy jargon ('compact facts') keeps it from being fully crisp.

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?

The clause 'Fact lookup does not establish local identity' hints that identity-related work belongs to the identity siblings, which is useful implied routing. However, no sibling is named and no explicit when-to-use/when-not condition is given, so the agent must infer the boundary itself.

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