editor_selection

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

Annotations already declare readOnlyHint, idempotentHint, openWorldHint=false and destructiveHint=false, so safety is covered. The description adds real value by disclosing the return value ('session context token') and an explicit limitation, but it omits what happens when zero or multiple entities are selected, given the stated 'exactly one' constraint.

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 short sentences with no filler, and the core action plus the 'exactly one' constraint is front-loaded ahead of the return value and limitation. The compression into 'document/entity identity' is slightly cryptic but costs nothing in length.

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 no parameters and no output schema, the description should fully carry the burden, and it does state the returned token and one limitation. It leaves important gaps: what types of entities exist, what the token is used for downstream, and error behavior when the selection is empty or multiple. Those gaps matter for an agent deciding whether it can call this at all.

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?

The tool takes zero parameters, so the baseline is 4 and there are no argument semantics that need explaining. The description usefully clarifies that selection state must already exist in the editor rather than being passed in, which is the relevant semantic point for a parameterless tool.

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 a verb ('Capture') and a resource ('selected entity') and states the scope ('exactly one'), but 'capture' is non-standard and 'entity' is never defined, so an agent cannot confidently infer this reads the editor's current selection. It also does not differentiate itself from siblings such as editor_has_member or editor_read_entry, which could plausibly be confused with it.

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?

There is no positive statement of when to call this versus the many editor_* siblings, and no prerequisites such as a required active selection. The only guidance is a negative limitation ('document filename discovery is not supported'), which hints at usage boundaries but does not route the agent to an alternative.

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