update_profile

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

The description goes beyond the annotations by disclosing the 2000-character cap, the truncated:true response flag, the sanitizer behavior shared with store, and that discarded content is not stored elsewhere. This gives the agent actionable information about side effects and output, though it does not describe auth needs or full response behavior.

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 reasonably concise and front-loaded with the core purpose, then adds the critical truncation behavior. The phrasing 'when the cap bit — branch on it' is slightly awkward, but every sentence contributes meaningful information without redundancy.

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 save operation with no output schema, the description covers the main behavioral caveat the agent must handle: truncation and the truncated:true flag. It does not specify the success response shape or whether an existing profile is overwritten, which are minor gaps but not blocking for invoking the tool correctly.

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 coverage is 100%, so the baseline is 3. The description adds value beyond the schema by naming the constant CPERSONA_MAX_PROFILE_LENGTH, mentioning the shared sanitizer, and warning that the discarded remainder is not persisted. It does not add detail on session_key, but the schema already explains it adequately.

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 says the tool saves a pre-computed agent profile to the database, with a specific verb, resource, and scope. It does not explicitly differentiate update_profile from its sibling store, though the 'pre-computed' qualifier and the reference to store's sanitizer imply a distinct role.

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 intended use is implied: call this when you already have a pre-computed agent profile to save. However, it does not explicitly state when to prefer this over store or any other sibling, nor does it give exclusions or alternatives.

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