Search Saved Messages (with tag filter)

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

With annotations declaring `readOnlyHint: true` and `openWorldHint: true`, the description adds valuable behavioral context beyond these: it specifies the search scope (`me`), the combination of query and tag filters, and the `newest first` ordering. It does not elaborate on rate limits or pagination, but the provided details meaningfully extend the annotation baseline.

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 two sentences long, front-loaded with the core action, and contains no filler. Every sentence adds useful information: scope, filter combination, and ordering. It is optimally concise for the tool's complexity.

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?

The description covers the core functionality but omits important details for a tool with 8 optional parameters and no output schema. It explains the main use case but does not describe the meaning of date range or limit parameters, nor what the response contains. Given the absence of an output schema and the low schema coverage, the description could be more complete, but it does establish the essential behavior.

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?

With schema description coverage at only 38%, the description needed to compensate for the undocumented parameters. It clarifies the relationship between `query`, `tagEmoji`, and `tagCustomEmojiIds` (combinable filters), but gives no guidance on `limit`, `maxDate`, `minDate`, `accountId`, or `savedPeer` (though `savedPeer` has a schema description). The description only partially covers the parameter space, leaving several parameters' semantics unexplained.

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 clearly states the tool's function: 'Search inside Saved Messages (`me`).' It specifies the scope (Saved Messages), the optional tag filtering mechanism, and the result ordering ('Newest first'). This differentiates it from sibling tools like `search_messages` (general search) and `get_saved_history` (browsing without search).

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 clear context: this tool is for searching within Saved Messages, with the ability to combine a free-text query with tag emoji/custom-emoji IDs. It implies when to use it (when targeting Saved Messages) but does not explicitly name alternatives or exclusions. The scope is well-defined, so the agent can infer appropriate use.

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