fiji_objects

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

Annotations already cover safety (readOnlyHint=true, openWorldHint=false), so the bar is lower, and the description adds real context: the two output shapes (per-type counts vs. objects by name) and the domain mapping that an ABBA session is a MultiSlicePositioner. It lacks detail on what a viewer/session object looks like, but the added semantics are meaningful.

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?

Two dense sentences, front-loaded with the resource statement followed by the branch semantics. Every clause is informative, though the parenthetical omissions and the trailing ABBA sentence slightly interrupt flow.

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?

With one optional parameter, no output schema, and full annotation coverage, the description supplies enough to call the tool correctly in both modes. It explains what each branch returns, which compensates for the missing output schema; only object detail is left unspecified.

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 baseline is 3, but the description adds meaning beyond the schema by clarifying that returned objects are identified 'by the names module inputs accept,' which links the type values to the module tools. It goes slightly beyond the schema's example-based description without adding format syntax.

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 the resource precisely (live objects Fiji holds: images, viewers, sessions) and spells out the two modes of behavior. The verb is implicit rather than explicit ('list/query'), and it does not name a sibling to distinguish from, but the resource and scope are unambiguous.

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 implied by the two-mode branch on the type parameter (count vs. retrieve), which tells an agent when each behavior fires. However, it never states when to reach for this tool instead of fiji_module_search or fiji_module_describe, so the agent must infer the boundary.

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