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

Annotations already declare readOnly, idempotent, non-destructive, closed-world, so the description clears the lower bar easily by adding real edge-case semantics: a missing profile yields an empty result rather than an error, while missing or foreign-workspace IDs produce a distinct 'party_not_found'. It also discloses that restricted-content references are withheld and that profile facts never post, which an agent could not infer from the annotations.

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?

Four short sentences, front-loaded with the verb, resource and identifier provenance, followed by return contents and then failure modes. Dense but nearly every clause carries information; the closing 'Profile facts never change who a party is and never post' is slightly cryptic phrasing for what is really a no-side-effects guarantee.

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 an output schema present, the description need not explain return shapes, and it correctly focuses on the things structured data cannot express: empty-vs-error semantics, the party_not_found case, and content withholding. Coverage is strong for a two-parameter read tool; only explicit guidance on when not to use it is absent.

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 100%, and the schema already documents both the party_id and workspace_tag semantics. The description only repeats that party_id originates from list_parties, adding nothing about format or validation beyond the structured fields, so the baseline 3 applies.

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 and resource ('Looks up a workspace party by party_id') and enumerates what comes back: current non-posting profile, source assertions, hashes and conflicts. It also anchors the identifier to the sibling that produces it ('from list_parties'), so the agent can tell it apart from the list tool without opening a schema.

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 'by party_id (from list_parties)' phrasing establishes the natural call sequence: list first, then fetch details. It gives clear context for when this tool is the right one, but names no explicit exclusion or alternative for retrieving party data in bulk.

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