Attest that a phrasing/id denotes an existing object

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

Annotations already declare readOnlyHint=false, idempotentHint=true, and destructiveHint=false, establishing the operation as a non-destructive mutation. The description adds meaningful context beyond the annotations, explaining that it 'Builds the shared reference graph' and ensures future `emem_entity_resolve` calls converge. No contradiction with annotations; the added context about graph construction and long-term effect is valuable.

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 description is well-structured with a clear headline, a 'When to use' paragraph, and a concrete example. It is front-loaded with the core purpose, and every sentence serves a distinct role: definition, usage context, and illustration. No filler or redundancy; appropriately sized for the tool's complexity.

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 tool with a nested object and no output schema, the description covers the purpose, usage scenarios, example arguments, and how it relates to the resolve tool. It does not describe return values, but since this is a mutation tool without an output schema, that is not a significant gap. It could be more explicit about idempotency or signing, but annotations fill some gaps, making it adequately complete.

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 the baseline is 3. The description adds value by naming the specific external id types (GERS / OSM / Wikidata) that map to the nested `external_ids` parameter, and the example arguments demonstrate the intended structure for `entity_token` and `alias`. The description clarifies that `alias` is an alternate label, which reinforces but also goes slightly beyond the schema's brief descriptions.

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 clearly states the tool's purpose with a specific verb-resource pair: 'Record a signed equivalence: bind an alternate label or a stable external id ... to an existing canonical object.' It explicitly mentions the consumer tool `emem_entity_resolve`, distinguishing this from sibling tools by explaining how it feeds the resolve process. The title and description align well.

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 description provides a dedicated 'When to use' section with concrete scenarios ('when you learn that two phrasings denote the same object' or 'to attach an authoritative external id'). It clearly sets the context but does not explicitly state when NOT to use it or name alternative tools for exclusion. This matches the 'clear context, no exclusions' level.

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