chat_list_sessions

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

With no annotations, the description carries the full behavioral burden. It clearly discloses that the tool only reads local JSON files, does not mutate Unreal, does not call providers, and does not spend credits. This gives an agent a precise safety profile, though it does not discuss failure modes or data freshness.

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 compact and front-loaded with the core purpose, followed by a short use case, a safety note, a KB pointer, and an example. Every sentence adds useful context; there is no filler.

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 simple read-only list tool with an output schema, the description is largely complete: it gives the use case, safety profile, data source, and a call example. The main gap is the lack of explicit explanation for `limit`, but that is inferable from the schema and context.

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 0%, so the description must compensate. It mentions 'optional IDE companion ledgers,' which maps to include_ide_companion_ledgers, but it never explains `limit` or how the parameters interact. The parameter names and defaults are self-explanatory but not semantically elaborated.

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: 'List saved MCP Chat sessions and optional IDE companion ledgers.' It also gives an immediate use case ('drive an editor-side session picker before resuming a companion workflow') that helps distinguish it from sibling chat tools.

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?

It explicitly says when to use the tool: to drive an editor-side session picker before resuming a companion workflow. It does not name specific alternatives or exclusions, but the clear context and read-only safety note are sufficient guidance for most agents.

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