tabs_context

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

With no annotations, the description carries the behavioral disclosure burden. It discloses the stable nature of tab ids, which is valuable state-related information, and the listed output fields clarify what the call returns. It does not mention read-only status explicitly, but the verb 'List' and the absence of mutation language make the behavior reasonably clear.

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 deliver the resource, returned fields, and the critical usage instruction without any filler. Every part earns its place.

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 zero-parameter list tool with no output schema, the description is complete: it names the output fields and the key behavioral fact (stable ids), which is all an agent needs to invoke it correctly and use the results with sibling tools.

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 has zero parameters, so the description does not need to compensate for undocumented inputs. The baseline of 4 applies, and no parameter explanation is required.

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 ('List'), resource ('Firefox tabs'), and enumerates the returned fields (id, url, title, active). This clearly differentiates it from sibling tab management tools like tabs_create, tabs_close, and tabs_activate.

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?

Provides clear usage guidance: 'Call this first' and explains that tab ids are stable while the server runs, which signals that this tool should be used to obtain tab identifiers for later operations. It does not explicitly name alternatives or exclusion cases, but the context strongly implies its role relative to sibling tabs_* tools.

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