add_custom_domainAttach or replace the app custom domain through the same Fine Structure Studio custom-domain flow. Returns exact DNS verification and routing records for the user to configure at their DNS provider.
| Name | Required | Description | Default |
|---|---|---|---|
| app_id | Yes | The app ID | |
| domain | Yes | Custom domain to connect, for example example.com or app.example.com |
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
The description adds value beyond the annotations by mentioning the return of exact DNS records and referencing the Fine Structure Studio flow, which implies a guided process. Annotations already cover the destructive nature (destructiveHint=true), and the description's 'attach or replace' is consistent. It does not describe side effects of replacement (e.g., whether the old domain is removed) but provides useful context about output.
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 extremely concise with two sentences, front-loading the core action and then the key output. Every word adds value 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 tool with only two parameters, no output schema, and annotations that cover safety, the description is fairly complete. It explains the action and the return value. Minor gaps remain, such as not clarifying behavior when replacing an existing domain or the need for prior ownership verification, but these are not critical for correct invocation.
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%; both parameters are documented in the schema. The tool description does not add additional semantics beyond what the schema provides (e.g., the domain format is already in the parameter description). Thus, a baseline score of 3 is appropriate.
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 a specific action ('attach or replace') on a specific resource ('the app custom domain'), and even notes the return of DNS records. It implicitly distinguishes from sibling tools like remove_custom_domain and set_primary_domain by its action and purpose.
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 indicates what the tool does but does not explicitly say when to use it versus alternatives. It does not name sibling tools like remove_custom_domain or set_primary_domain, nor does it state when not to use it. The context is clear enough that an agent could infer, but there is no direct guidance.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
Add one secure layer between your agents and this server.
Most tools have clearly distinct purposes with detailed descriptions, but there are some overlapping pairs like read_app_file/read_app_files and create_entity_records vs seed_entity, which could cause misselection. Singular/plural variants and compatibility tools introduce minor ambiguity, but the majority are well-separated.
Tool names predominantly follow a consistent verb_noun pattern (e.g., create_app, get_entities, delete_secret). There are some variations like 'agency_create_client' and 'seed_entity' that deviate slightly, but the overall convention is predictable and readable.
With 82 tools, the server is far above the typical range and feels overwhelming. Even for a full platform API, the count is extreme and likely increases selection complexity. A more curated set would improve navigability without sacrificing capability.
The tool surface is exceptionally comprehensive, covering app lifecycle, file operations, entity CRUD, versioning, A/B testing, secrets, integrations, domains, agents, scheduling, policies, and member management. No obvious missing operations for the platform's scope; it even includes validation and workflow guidance tools.