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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint. The description adds one useful behavioral detail—'with recall_mode disclosure'—indicating the response reveals which retrieval mode(s) produced results. It does not, however, explain how the fusion works (e.g., result merging, scoring interaction), so it provides only modest value beyond the annotations.

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 a single sentence with no filler, and the core action 'Fused recall' is front-loaded. Every word contributes meaning, but the extreme brevity edges toward under-specification, so it does not quite earn 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?

Despite having an output schema and 100% schema description coverage, this is a complex 9-parameter tool with multiple retrieval modes. The description omits critical context such as when to prefer this over memory.search, how the fused modes interact, or what 'recall_mode disclosure' concretely means in the response. Significant gaps remain for an agent deciding whether and how to invoke this tool.

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 100%, so all 9 parameters are already documented in the input schema. The description's mention of the four retrieval modes adds context for the query parameter, but it does not add per-parameter meaning beyond what the schema provides. Baseline 3 applies.

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 states a specific verb and resource: 'fused recall across full-text, vector, graph, and coordinate lookup.' This clearly distinguishes the tool from a plain memory.search by emphasizing its multi-modal hybrid nature. However, it does not explicitly name a sibling tool or contrast itself, so it stops short of a perfect score.

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 no explicit when-to-use guidance, no exclusions, and no mention of alternative tools like memory.search or memory.list. The 'fused' wording implies a use case, but the agent is left to infer when this hybrid approach is appropriate vs a single-mode search.

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