get_identity

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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false. The description adds 'Read-only, local' (local is extra), explains that fields may be empty strings, describes the {} return for no account, and clarifies the file_paths semantics referencing list_knowledge_files. This goes beyond the annotations without contradicting them.

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 tightly written paragraphs: the first defines purpose and context in one sentence, the second details return structure and edge cases. No filler or redundancy; every sentence adds value.

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 no output schema, the description carries the burden of return format, and it does so comprehensively: field names, types (strings, file_paths), empty-string behavior, {} for no account, and reference to list_knowledge_files. Nothing an agent needs to call it correctly is missing.

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 schema description for account_id already fully explains the parameter ('integer id from list_accounts', omit/null = active account) with 100% coverage. The tool description adds no further parameter detail, so the baseline of 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?

The description uses a specific verb ('Return') and resource ('user's self-description for an account'), then enumerates the exact fields (who_am_i, what_i_do, tone, key_info, file_paths) and their purpose ('context for drafting replies in their voice'). This clearly distinguishes it from sibling tools like list_accounts or list_knowledge_files, even though it doesn't name them.

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 states when to use it ('context for drafting replies in their voice') and indirectly points to an alternative ('see list_knowledge_files' for file paths). It doesn't explicitly say when not to use it, but the context is clear enough for an agent to choose it appropriately.

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