context_list

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

With no annotations provided, the description carries the full burden, and it fulfills it well. It explicitly states the operation is read-only and discloses that full values are never returned, which is a meaningful behavioral guarantee that prevents an agent from expecting content leaks.

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 sentences with no wasted words. The action and resource are front-loaded, the return format is compactly summarized, the safety constraint is explicit, and the usage scenario is included in a natural way.

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 no-parameter, read-only listing tool, this description covers naming, output scope, constraints, and use case. An agent has everything needed to decide when to call it and what to expect.

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 and the schema is fully covered, so there is nothing for the description to add. Per the baseline for zero-parameter tools, this is appropriate.

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 specific verb ('List'), a specific resource ('shared context store'), and enumerates exactly what is returned (key, size, age, description). It also explicitly excludes full values, which distinguishes it from context_read. This leaves no ambiguity about what the tool does.

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 gives an explicit use case: discover available context before re-pasting and reference via `context_ref`. It does not explicitly state when to use context_read instead, but the statement 'never the full value' gives a strong implicit contrast with the read sibling.

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