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

Annotations already disclose this is a non-read-only, non-idempotent, non-destructive write, so the safety profile is covered. The description usefully adds the same-store/space and visibility preconditions, but says nothing about behavior on duplicate links (relevant given idempotentHint=false) or whether 'explicit' differs from implicitly inferred links.

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, front-loaded with the verb and resource, with no filler. The capitalized 'Free' is ambiguous and slightly muddies an otherwise clean line, and the preconditions are packed in without losing clarity.

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 write operation with no output schema, the definition covers the core action and its preconditions but omits what the call returns, whether duplicate links error or are created, and how edge_kind choices behave. Adequate to call, incomplete to call confidently.

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 nominally 100%, but the per-parameter text is boilerplate ('Input value for the Link Memories tool'), so the schema adds little real meaning. The description indirectly maps to the two memory-id params via 'between two visible personal Memories' but never explains edge_kind or its default value of 'references', leaving it opaque.

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 (Create) and resource (an explicit link between two Memories) with clear scope constraints (same owning store/space, visible, personal). Siblings like remove_memory_relationship and update_memory_relationship imply a relationship family, but the description never names them, so the agent gets no direct sibling contrast.

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 usage context is only implied by preconditions ('two visible personal Memories in the same owning store/space') rather than stated as when-to-use. There is no guidance on when to link versus update_memory_relationship / memory_relationships, nor what to do when a link already exists.

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